diff --git a/src/channels/chan_voicemngr.c b/src/channels/chan_voicemngr.c
index 2cfc303cd43358a722931c074473802434b02aed..37b8ea3de1bf8372408ed900302d3cfed6e0a9de 100644
--- a/src/channels/chan_voicemngr.c
+++ b/src/channels/chan_voicemngr.c
@@ -3558,7 +3558,7 @@ static void chan_voicemngr_process_event(const struct endpt_event *ev, const cha
 		case EVENT_OFFHOOK: {
 			int sip_client_id = -1;
 
-			if (data && strcmp(data, "narrow_band_only") == 0) {
+			if (data && strcmp(data, EVENT_DATA_NARROW_BAND_ONLY) == 0) {
 				p->flags |= VOICEMNGR_CHAN_FLAG_NARROW_BAND_ONLY;
 				ast_debug(3, "the terminal which goes off hook supports narrow band only\n");
 			} else {