diff --git a/src/osmo_gsm_tester/templates/osmo-bsc.cfg.tmpl b/src/osmo_gsm_tester/templates/osmo-bsc.cfg.tmpl
index 53e683b..572e765 100644
--- a/src/osmo_gsm_tester/templates/osmo-bsc.cfg.tmpl
+++ b/src/osmo_gsm_tester/templates/osmo-bsc.cfg.tmpl
@@ -118,5 +118,6 @@
  amr-config 5_90k allowed
  amr-config 5_15k forbidden
  amr-config 4_75k forbidden
+ osmux ${bsc.use_osmux}
  msc-addr msc_remote
  bsc-addr bsc_local