diff --git a/openbsc/src/input/misdn.c b/openbsc/src/input/misdn.c
index fa8aca0..b36bdf8 100644
--- a/openbsc/src/input/misdn.c
+++ b/openbsc/src/input/misdn.c
@@ -247,7 +247,7 @@
 	/* set tx delay timer for next event */
 	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
 	e1i_ts->sign.tx_timer.data = e1i_ts;
-	bsc_schedule_timer(&e1i_ts->sign.tx_timer, 0, 50000);
+	bsc_schedule_timer(&e1i_ts->sign.tx_timer, 0, e1i_ts->sign.delay);
 
 	return ret;
 }
@@ -387,6 +387,7 @@
 struct e1inp_driver misdn_driver = {
 	.name = "mISDNuser",
 	.want_write = ts_want_write,
+	.default_delay = 50000,
 };
 
 static int mi_e1_setup(struct e1inp_line *line, int release_l2)