diff --git a/openbsc/src/libbsc/abis_rsl.c b/openbsc/src/libbsc/abis_rsl.c
index 664b1a6..868375f 100644
--- a/openbsc/src/libbsc/abis_rsl.c
+++ b/openbsc/src/libbsc/abis_rsl.c
@@ -2048,7 +2048,7 @@
 	dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof(*dh));
 	init_dchan_hdr(dh, msg_type);
 	dh->c.msg_discr = ABIS_RSL_MDISC_DED_CHAN;
-	dh->chan_nr = gsm_ts2chan_nr(ts, 0);
+	dh->chan_nr = gsm_pchan2chan_nr(GSM_PCHAN_PDCH, ts->nr, 0);
 
 	DEBUGP(DRSL, "%s IPAC PDCH %sACT\n", gsm_ts_name(ts),
 		act ? "" : "DE");