diff --git a/src/call.c b/src/call.c
index 487be56..74c0a08 100644
--- a/src/call.c
+++ b/src/call.c
@@ -179,6 +179,4 @@ void call_leg_update_sdp(struct call_leg *leg, const char *sdp)
 	if (!sdp || !*sdp)
 		return;
 	OSMO_STRLCPY_ARRAY(leg->sdp, sdp);
-	LOGP(DAPP, LOGL_NOTICE, "call(%u) leg(0x%p) received SDP: %s\n",
-	     leg->call->id, leg, leg->sdp);
 }
diff --git a/src/sdp.c b/src/sdp.c
index 46330cd..1629c2e 100644
--- a/src/sdp.c
+++ b/src/sdp.c
@@ -32,223 +32,86 @@
 
 #include <string.h>
 
-/*
- * Check if the media mode attribute exists in SDP, in this
- * case update the passed pointer with the media mode
- */
-bool sdp_get_sdp_mode(const sip_t *sip, sdp_mode_t *mode) {
+static const struct value_string sdp_mode_attr[] = {
+	{ SDP_MODE_UNSET, ""},
+	{ SDP_MODE_INACTIVE, "a=inactive\r\n"},
+	{ SDP_MODE_SENDRECV, "a=sendrecv\r\n"},
+	{ SDP_MODE_SENDONLY, "a=sendonly\r\n"},
+	{ SDP_MODE_RECVONLY, "a=recvonly\r\n"},
+	{}
+};
 
-	const char *sdp_data;
-	sdp_parser_t *parser;
-	sdp_session_t *sdp;
+const struct value_string sdp_mode_names[] = {
+	{ SDP_MODE_UNSET, "unset"},
+	{ SDP_MODE_INACTIVE, "inactive"},
+	{ SDP_MODE_SENDRECV, "sendrecv"},
+	{ SDP_MODE_SENDONLY, "sendonly"},
+	{ SDP_MODE_RECVONLY, "recvonly"},
+	{}
+};
 
-	if (!sip->sip_payload || !sip->sip_payload->pl_data) {
-		LOGP(DSIP, LOGL_ERROR, "No SDP file\n");
-		return false;
-	}
-
-	sdp_data = sip->sip_payload->pl_data;
-	parser = sdp_parse(NULL, sdp_data, strlen(sdp_data), sdp_f_mode_0000);
-	if (!parser) {
-		LOGP(DSIP, LOGL_ERROR, "Failed to parse SDP\n");
-		return false;
-	}
-
-	sdp = sdp_session(parser);
-	if (!sdp) {
-		LOGP(DSIP, LOGL_ERROR, "No sdp session\n");
-		sdp_parser_free(parser);
-		return false;
-	}
-
-	if (!sdp->sdp_media || !sdp->sdp_media->m_mode) {
-		sdp_parser_free(parser);
-		return sdp_sendrecv;
-	}
-
-	sdp_parser_free(parser);
-	*mode = sdp->sdp_media->m_mode;
-	return true;
-}
-
-/*
- * We want to decide on the audio codec later but we need to see
- * if it is even including some of the supported ones.
- */
-bool sdp_screen_sdp(const sip_t *sip)
+/* Return location of a given SDP sendrecv mode attribute, if any. */
+const char *sdp_find_mode(const char *sdp_str, enum sdp_mode mode)
 {
-	const char *sdp_data;
-	sdp_parser_t *parser;
-	sdp_session_t *sdp;
-	sdp_media_t *media;
+	const char *found;
+	if (mode == SDP_MODE_UNSET)
+		return NULL;
 
-	if (!sip->sip_payload || !sip->sip_payload->pl_data) {
-		LOGP(DSIP, LOGL_ERROR, "No SDP file\n");
-		return false;
-	}
+	found = strstr(sdp_str, get_value_string(sdp_mode_attr, mode));
+	if (!found)
+		return NULL;
 
-	sdp_data = sip->sip_payload->pl_data;
-	parser = sdp_parse(NULL, sdp_data, strlen(sdp_data), 0);
-	if (!parser) {
-		LOGP(DSIP, LOGL_ERROR, "Failed to parse SDP\n");
-		return false;
-	}
+	/* At the start of the line? */
+	if (found > sdp_str && *(found-1) != '\n')
+		return NULL;
 
-	sdp = sdp_session(parser);
-	if (!sdp) {
-		LOGP(DSIP, LOGL_ERROR, "No sdp session\n");
-		sdp_parser_free(parser);
-		return false;
-	}
-
-	for (media = sdp->sdp_media; media; media = media->m_next) {
-		sdp_rtpmap_t *map;
-
-		if (media->m_proto != sdp_proto_rtp)
-			continue;
-		if (media->m_type != sdp_media_audio)
-			continue;
-
-		for (map = media->m_rtpmaps; map; map = map->rm_next) {
-			if (strcasecmp(map->rm_encoding, "GSM") == 0)
-				goto success;
-			if (strcasecmp(map->rm_encoding, "GSM-EFR") == 0)
-				goto success;
-			if (strcasecmp(map->rm_encoding, "GSM-HR-08") == 0)
-				goto success;
-			if (strcasecmp(map->rm_encoding, "AMR") == 0)
-				goto success;
-		}
-	}
-
-	sdp_parser_free(parser);
-	return false;
-
-success:
-	sdp_parser_free(parser);
-	return true;
+	return found;
 }
 
-bool sdp_extract_sdp(struct sip_call_leg *leg, const sip_t *sip, bool any_codec)
+/* Return the last SDP sendrecv mode attribute, or SDP_MODE_UNSET */
+enum sdp_mode sdp_get_mode(const char *sdp_str, const char **found_at)
 {
-	sdp_connection_t *conn;
-	sdp_session_t *sdp;
-	sdp_parser_t *parser;
-	sdp_media_t *media;
-	const char *sdp_data;
-	bool found_conn = false, found_map = false;
-
-	if (!sip->sip_payload || !sip->sip_payload->pl_data) {
-		LOGP(DSIP, LOGL_ERROR, "leg(%p) but no SDP file\n", leg);
-		return false;
-	}
-
-	sdp_data = sip->sip_payload->pl_data;
-	parser = sdp_parse(NULL, sdp_data, strlen(sdp_data), 0);
-	if (!parser) {
-		LOGP(DSIP, LOGL_ERROR, "leg(%p) failed to parse SDP\n",
-			leg);
-		return false;
-	}
-
-	sdp = sdp_session(parser);
-	if (!sdp) {
-		LOGP(DSIP, LOGL_ERROR, "leg(%p) no sdp session\n", leg);
-		sdp_parser_free(parser);
-		return false;
-	}
-
-	for (conn = sdp->sdp_connection; conn; conn = conn->c_next) {
-		struct in_addr addr;
-
-		if (conn->c_addrtype != sdp_addr_ip4)
+	const char *at = NULL;
+	enum sdp_mode mode = SDP_MODE_UNSET;
+	enum sdp_mode i;
+	for (i = 0; i < SDP_MODES_COUNT; i++) {
+		const char *found = sdp_find_mode(sdp_str, i);
+		if (!found)
 			continue;
-		inet_aton(conn->c_address, &addr);
-		leg->base.ip = addr.s_addr;
-		found_conn = true;
-		break;
-	}
-
-	for (media = sdp->sdp_media; media; media = media->m_next) {
-		sdp_rtpmap_t *map;
-
-		if (media->m_proto != sdp_proto_rtp)
+		/* If more than one sendrecv attrib are in the SDP string, let the last one win */
+		if (at > found)
 			continue;
-		if (media->m_type != sdp_media_audio)
-			continue;
-
-		for (map = media->m_rtpmaps; map; map = map->rm_next) {
-			if (!any_codec && strcasecmp(map->rm_encoding, leg->wanted_codec) != 0)
-				continue;
-
-			leg->base.port = media->m_port;
-			leg->base.payload_type = map->rm_pt;
-			found_map = true;
-			break;
-		}
-
-		if (found_map)
-			break;
+		at = found;
+		mode = i;
 	}
 
-	if (!found_conn || !found_map) {
-		LOGP(DSIP, LOGL_ERROR, "leg(%p) did not find %d/%d\n",
-			leg, found_conn, found_map);
-		sdp_parser_free(parser);
-		return false;
-	}
-
-	sdp_parser_free(parser);
-	return true;
+	if (found_at)
+		*found_at = at;
+	return mode;
 }
 
-char *sdp_create_file(struct sip_call_leg *leg, struct call_leg *other, sdp_mode_t mode)
+/* Remove all pre-existing occurences of an SDP mode attribute, and then add the given mode attribute (if not
+ * SDP_MODE_UNSET). Allocate the resulting string from ctx (talloc). */
+char *sdp_copy_and_set_mode(void *ctx, const char *sdp_str, enum sdp_mode mode)
 {
-	struct in_addr net = { .s_addr = other->ip };
-	char *fmtp_str = NULL, *sdp;
-	char *mode_attribute;
-	char ip_addr[INET_ADDRSTRLEN];
+	char *removed = talloc_strdup(ctx, sdp_str);
+	char *added;
+	char *found_at;
 
-	inet_ntop(AF_INET, &net, ip_addr, sizeof(ip_addr));
-	leg->wanted_codec = app_media_name(other->payload_msg_type);
-
-	if (strcmp(leg->wanted_codec, "AMR") == 0)
-		fmtp_str = talloc_asprintf(leg, "a=fmtp:%d octet-align=1\r\n", other->payload_type);
-
-	switch (mode) {
-		case sdp_inactive:
-			mode_attribute = "a=inactive\r\n";
-			break;
-		case sdp_sendrecv:
-			mode_attribute = "a=sendrecv\r\n";
-			break;
-		case sdp_sendonly:
-			mode_attribute = "a=sendonly\r\n";
-			break;
-		case sdp_recvonly:
-			mode_attribute = "a=recvonly\r\n";
-			break;
-		default:
-			OSMO_ASSERT(false);
-			break;
+	/* Remove */
+	while (sdp_get_mode(removed, (const char**)&found_at) != SDP_MODE_UNSET) {
+		char *next_line = strchr(found_at, '\n');
+		if (!next_line)
+			*found_at = '\0';
+		else
+			strcpy(found_at, next_line);
 	}
 
-	sdp = talloc_asprintf(leg,
-				"v=0\r\n"
-				"o=Osmocom 0 0 IN IP4 %s\r\n"
-				"s=GSM Call\r\n"
-				"c=IN IP4 %s\r\n"
-				"t=0 0\r\n"
-				"m=audio %d RTP/AVP %d\r\n"
-				"%s"
-				"a=rtpmap:%d %s/8000\r\n"
-				"%s",
-				ip_addr, ip_addr,
-				other->port, other->payload_type,
-				fmtp_str ? fmtp_str : "",
-				other->payload_type,
-				leg->wanted_codec,
-				mode_attribute);
-	talloc_free(fmtp_str);
-	return sdp;
+	/* Add */
+	if (mode == SDP_MODE_UNSET)
+		return removed;
+
+	added = talloc_asprintf(ctx, "%s%s", removed, get_value_string(sdp_mode_attr, mode));
+	talloc_free(removed);
+	return added;
 }
diff --git a/src/sdp.h b/src/sdp.h
index 8e4e314..3247a75 100644
--- a/src/sdp.h
+++ b/src/sdp.h
@@ -1,15 +1,20 @@
 #pragma once
 
-#include <sofia-sip/sip.h>
-#include <sofia-sip/sdp.h>
+#include <osmocom/core/utils.h>
 
-#include <stdbool.h>
+enum sdp_mode {
+	SDP_MODE_UNSET = 0,
+	SDP_MODE_INACTIVE,
+	SDP_MODE_SENDRECV,
+	SDP_MODE_SENDONLY,
+	SDP_MODE_RECVONLY,
+	SDP_MODES_COUNT,
+};
 
-struct sip_call_leg;
-struct call_leg;
+extern const struct value_string sdp_mode_names[];
+static inline const char *sdp_mode_name(enum sdp_mode mode)
+{ return get_value_string(sdp_mode_names, mode); }
 
-bool sdp_get_sdp_mode(const sip_t *sip, sdp_mode_t *mode);
-bool sdp_screen_sdp(const sip_t *sip);
-bool sdp_extract_sdp(struct sip_call_leg *leg, const sip_t *sip, bool any_codec);
-
-char *sdp_create_file(struct sip_call_leg *, struct call_leg *, sdp_mode_t mode);
+const char *sdp_find_mode(const char *sdp_str, enum sdp_mode mode);
+enum sdp_mode sdp_get_mode(const char *sdp_str, const char **found_at);
+char *sdp_copy_and_set_mode(void *ctx, const char *sdp_str, enum sdp_mode mode);
diff --git a/src/sip.c b/src/sip.c
index 46e4277..072b8ab 100644
--- a/src/sip.c
+++ b/src/sip.c
@@ -104,7 +104,6 @@ static void new_call(struct sip_agent *agent, nua_handle_t *nh,
 	struct call *call;
 	struct sip_call_leg *leg;
 	const char *from = NULL, *to = NULL;
-	char ip_addr[INET_ADDRSTRLEN];
 
 	LOGP(DSIP, LOGL_INFO, "Incoming call(%s) handle(%p)\n", sip->sip_call_id->i_id, nh);
 
@@ -146,11 +145,10 @@ static void new_call(struct sip_agent *agent, nua_handle_t *nh,
 
 static void sip_handle_reinvite(struct sip_call_leg *leg, nua_handle_t *nh, const sip_t *sip) {
 
+	const char *reinvite_sdp;
 	char *sdp;
-	sdp_mode_t mode = sdp_sendrecv;
-	uint32_t ip = leg->base.ip;
-	uint16_t port = leg->base.port;
-	char ip_addr[INET_ADDRSTRLEN];
+	enum sdp_mode mode;
+	enum sdp_mode mode_other;
 
 	LOGP(DSIP, LOGL_INFO, "re-INVITE for call %s\n", sip->sip_call_id->i_id);
 
@@ -162,11 +160,12 @@ static void sip_handle_reinvite(struct sip_call_leg *leg, nua_handle_t *nh, cons
 		return;
 	}
 
-	if (!sdp_get_sdp_mode(sip, &mode)) {
+	reinvite_sdp = sip_get_sdp(sip);
+	if (!reinvite_sdp) {
 		/* re-INVITE with no SDP.
 		 * We should respond with SDP reflecting current session
 		 */
-		sdp = sdp_create_file(leg, other, sdp_sendrecv);
+		sdp = sdp_copy_and_set_mode(leg, other->sdp, SDP_MODE_SENDRECV);
 		nua_respond(nh, SIP_200_OK,
 			    NUTAG_MEDIA_ENABLE(0),
 			    SIPTAG_CONTENT_TYPE_STR("application/sdp"),
@@ -176,37 +175,32 @@ static void sip_handle_reinvite(struct sip_call_leg *leg, nua_handle_t *nh, cons
 		return;
 	}
 
-	struct in_addr net = { .s_addr = leg->base.ip };
-	inet_ntop(AF_INET, &net, ip_addr, sizeof(ip_addr));
-	LOGP(DSIP, LOGL_DEBUG, "pre re-INVITE have IP:port (%s:%u)\n", ip_addr, leg->base.port);
+	mode = sdp_get_mode(reinvite_sdp, NULL);
 
-	call_leg_update_sdp(&leg->base, sip_get_sdp(sip));
+	call_leg_update_sdp(&leg->base, reinvite_sdp);
 
-	if (mode == sdp_sendonly) {
+	switch (mode) {
+	case SDP_MODE_SENDONLY:
 		/* SIP side places call on HOLD */
-		sdp = sdp_create_file(leg, other, sdp_recvonly);
-		/* TODO: Tell core network to stop sending RTP ? */
-	} else {
-		/* SIP re-INVITE may want to change media, IP, port */
-		if (!sdp_extract_sdp(leg, sip, true)) {
-			LOGP(DSIP, LOGL_ERROR, "leg(%p) no audio, releasing\n", leg);
-			nua_respond(nh, SIP_406_NOT_ACCEPTABLE, TAG_END());
-			nua_handle_destroy(nh);
-			call_leg_release(&leg->base);
-			return;
-		}
-		struct in_addr net = { .s_addr = leg->base.ip };
-		inet_ntop(AF_INET, &net, ip_addr, sizeof(ip_addr));
-		LOGP(DSIP, LOGL_DEBUG, "Media IP:port in re-INVITE: (%s:%u)\n", ip_addr, leg->base.port);
-		if (ip != leg->base.ip || port != leg->base.port) {
-			LOGP(DSIP, LOGL_INFO, "re-INVITE changes media connection.\n");
-			if (other->update_rtp)
-				other->update_rtp(leg->base.call->remote);
-		}
-		sdp = sdp_create_file(leg, other, sdp_sendrecv);
+		mode_other = SDP_MODE_RECVONLY;
+		break;
+	case SDP_MODE_RECVONLY:
+		mode_other = SDP_MODE_SENDONLY;
+		break;
+	case SDP_MODE_INACTIVE:
+		mode_other = SDP_MODE_INACTIVE;
+		break;
+	default:
+		mode_other = SDP_MODE_SENDRECV;
+		break;
 	}
 
-	LOGP(DSIP, LOGL_DEBUG, "Sending 200 response to re-INVITE for mode(%u)\n", mode);
+	if (other->update_rtp)
+		other->update_rtp(leg->base.call->remote);
+
+	sdp = sdp_copy_and_set_mode(leg, other->sdp, mode_other);
+	LOGP(DSIP, LOGL_DEBUG, "Sending 200 response (%s) to re-INVITE with mode '%s'\n",
+	     sdp_mode_name(mode_other), sdp_mode_name(mode));
 	nua_respond(nh, SIP_200_OK,
 		    NUTAG_MEDIA_ENABLE(0),
 		    SIPTAG_CONTENT_TYPE_STR("application/sdp"),
@@ -472,17 +466,13 @@ static void sip_connect_call(struct call_leg *_leg)
 	OSMO_ASSERT(_leg->type == CALL_TYPE_SIP);
 	leg = (struct sip_call_leg *) _leg;
 
-	/*
-	 * TODO/FIXME: check if resulting codec is compatible..
-	 */
-
 	other = call_leg_other(&leg->base);
 	if (!other) {
 		sip_release_call(&leg->base);
 		return;
 	}
 
-	sdp = sdp_create_file(leg, other, sdp_sendrecv);
+	sdp = sdp_copy_and_set_mode(leg, other->sdp, SDP_MODE_SENDRECV);
 
 	leg->state = SIP_CC_CONNECTED;
 	nua_respond(leg->nua_handle, SIP_200_OK,
@@ -521,7 +511,7 @@ static void sip_hold_call(struct call_leg *_leg)
 		sip_release_call(&leg->base);
 		return;
 	}
-	char *sdp = sdp_create_file(leg, other_leg, sdp_sendonly);
+	char *sdp = sdp_copy_and_set_mode(leg, other_leg->sdp, SDP_MODE_SENDONLY);
 	nua_invite(leg->nua_handle,
 		    NUTAG_MEDIA_ENABLE(0),
 		    SIPTAG_CONTENT_TYPE_STR("application/sdp"),
@@ -543,7 +533,7 @@ static void sip_retrieve_call(struct call_leg *_leg)
 		sip_release_call(&leg->base);
 		return;
 	}
-	char *sdp = sdp_create_file(leg, other_leg, sdp_sendrecv);
+	char *sdp = sdp_copy_and_set_mode(leg, other_leg->sdp, SDP_MODE_SENDRECV);
 	nua_invite(leg->nua_handle,
 		    NUTAG_MEDIA_ENABLE(0),
 		    SIPTAG_CONTENT_TYPE_STR("application/sdp"),
@@ -566,7 +556,7 @@ static int send_invite(struct sip_agent *agent, struct sip_call_leg *leg,
 				called_num,
 				agent->app->sip.remote_addr,
 				agent->app->sip.remote_port);
-	char *sdp = sdp_create_file(leg, other, sdp_sendrecv);
+	char *sdp = sdp_copy_and_set_mode(leg, other->sdp, SDP_MODE_SENDRECV);
 
 	leg->state = SIP_CC_INITIAL;
 	leg->dir = SIP_DIR_MT;