diff --git a/drivers/isdn/hardware/mISDN/dsp_core.c b/drivers/isdn/hardware/mISDN/dsp_core.c
index 6c24687..3e0f54f 100644
--- a/drivers/isdn/hardware/mISDN/dsp_core.c
+++ b/drivers/isdn/hardware/mISDN/dsp_core.c
@@ -476,6 +476,11 @@ dsp_from_up(mISDNinstance_t *inst, struct sk_buff *skb)
 				}
 
 			} else {
+				if (dsp->features.pcm_id>=0) {
+					printk("Not sending Data to CMX -- > returning because of HW bridge\n");
+					dev_kfree_skb(skb);
+					break;
+				}
 				/* send data to tx-buffer (if no tone is played) */
 				spin_lock_irqsave(&dsp_obj.lock, flags);
 				if (!dsp->tone.tone) {