diff --git a/openbsc/src/libcommon/gsm_data_shared.c b/openbsc/src/libcommon/gsm_data_shared.c
index 1c4ade2..8264e42 100644
--- a/openbsc/src/libcommon/gsm_data_shared.c
+++ b/openbsc/src/libcommon/gsm_data_shared.c
@@ -169,6 +169,8 @@
 		ts->trx = trx;
 		ts->nr = k;
 		ts->pchan = GSM_PCHAN_NONE;
+		ts->dyn.pchan_is = GSM_PCHAN_NONE;
+		ts->dyn.pchan_want = GSM_PCHAN_NONE;
 		ts->tsc = -1;
 
 		gsm_mo_init(&ts->mo, bts, NM_OC_CHANNEL,