diff --git a/src/cnetz/dsp.c b/src/cnetz/dsp.c
index 8e7f2910..9b453bbf 100644
--- a/src/cnetz/dsp.c
+++ b/src/cnetz/dsp.c
@@ -34,8 +34,6 @@
 #include "telegramm.h"
 #include "dsp.h"
 
-extern int voice_deviation;
-
 /* test function to mirror received audio from ratio back to radio */
 //#define TEST_SCRAMBLE
 /* test the audio quality after cascading two scramblers (TEST_SCRAMBLE must be defined) */
@@ -721,12 +719,6 @@ again:
 			/* pre-emphasis is only used when scrambler is off, see FTZ 171 TR 60 Clause 4 */
 			if (cnetz->pre_emphasis && !cnetz->scrambler)
 				pre_emphasis(&cnetz->estate, speech_buffer, speech_length);
-			/* change level */
-			if (voice_deviation != 1) {
-				int j;
-				for (j = 0; j < speech_length; j++)
-					speech_buffer[j] *= (double)voice_deviation;
-			}
 			speech_pos = 0;
 		}
 		/* copy speech as long as we have something left in buffer */
@@ -796,7 +788,7 @@ void unshrink_speech(cnetz_t *cnetz, sample_t *speech_buffer, int count)
 	factor = cnetz->offset_factor;
 	for (i = 0; i < count; i++) {
 		/* change level */
-		x = speech_buffer[i] / (double)voice_deviation;
+		x = speech_buffer[i];
 		/* high-pass to remove low level frequencies, caused by level jump between audio chunks */
 		y = factor * (y_last + x - x_last);
 		x_last = x;
diff --git a/src/cnetz/main.c b/src/cnetz/main.c
index 31fc8788..8eaa4147 100644
--- a/src/cnetz/main.c
+++ b/src/cnetz/main.c
@@ -47,7 +47,6 @@ int set_clock_speed = 0;
 const char *flip_polarity = "auto";
 int ms_power = 0; /* 0..3 */
 int auth = 0;
-int voice_deviation = 1;
 
 void print_help(const char *arg0)
 {
@@ -76,9 +75,6 @@ void print_help(const char *arg0)
 	printf("        Enable authentication on the base station. Since we cannot\n");
 	printf("	authenticate, because we don't know the secret key and the algorithm,\n");
 	printf("	we just accept any card. With this we get the vendor IDs of the phone.\n");
-	printf(" -V --voice-deviation\n");
-	printf("	For some unknown reason, Siemens C5 use double deviation for voice.\n");
-	printf("	This option raises audio level on TX and lowers on RX.\n");
 	printf("\nstation-id: Give 7 digit station-id, you don't need to enter it for every\n");
 	printf("        start of this program.\n");
 	print_hotkeys_common();
@@ -98,7 +94,6 @@ static int handle_options(int argc, char **argv)
 		{"flip-polarity", 1, 0, 'F'},
 		{"ms-power", 1, 0, 'P'},
 		{"authentication", 0, 0, 'A'},
-		{"voice-deviation", 0, 0, 'V'},
 		{0, 0, 0, 0}
 	};
 
@@ -166,10 +161,6 @@ static int handle_options(int argc, char **argv)
 			auth = 1;
 			skip_args += 1;
 			break;
-		case 'V':
-			voice_deviation = 2;
-			skip_args += 1;
-			break;
 		default:
 			opt_switch_common(c, argv[0], &skip_args);
 		}