diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 45ed4731bb8c4b45bacc896ce3e404eefb87f122..9140f85f2269b101decb42db72fd6efac1c6436e 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -12114,16 +12114,22 @@ static struct ast_channel *sip_request_call(const char *type, int format, void *
 	char *dest = data;
 
 	oldformat = format;
-	format &= ((AST_FORMAT_MAX_AUDIO << 1) - 1);
-	if (!format) {
+	if ((format &= ((AST_FORMAT_MAX_AUDIO << 1) - 1))) {
 		ast_log(LOG_NOTICE, "Asked to get a channel of unsupported format %s while capability is %s\n", ast_getformatname(oldformat), ast_getformatname(global_capability));
 		return NULL;
 	}
-	if (!(p = sip_alloc(NULL, NULL, 0, SIP_INVITE)))
+	if (!(p = sip_alloc(NULL, NULL, 0, SIP_INVITE))) {
+		ast_log(LOG_ERROR, "Unable to build sip pvt data for '%s' (Out of memory)\n", (char *)data);
+		*cause = AST_CAUSE_CONGESTION;
 		return NULL;
+	}
 
-	if (!(p->options = ast_calloc(1, sizeof(*p->options))))
+	if (!(p->options = ast_calloc(1, sizeof(*p->options)))) {
+		sip_destroy(p);
+		ast_log(LOG_ERROR, "Unable to build option SIP data structure - Out of memory\n");
+		*cause = AST_CAUSE_CONGESTION;
 		return NULL;
+	}
 
 	ast_copy_string(tmp, dest, sizeof(tmp));
 	host = strchr(tmp, '@');