diff --git a/ddbridge/ddbridge-modulator.c b/ddbridge/ddbridge-modulator.c
index 7127675..3c06ec6 100644
--- a/ddbridge/ddbridge-modulator.c
+++ b/ddbridge/ddbridge-modulator.c
@@ -643,7 +643,7 @@ static int mod_set_attenuator(struct ddb *dev, u32 Value)
 			.mod_stream = 0,
 			.mod_setup_output = {
 				.connector = MOD_CONNECTOR_F,
-				.num_channels = 24,
+				.num_channels = dev->link[0].info->port_num,
 				.unit = MOD_UNIT_DBUV,
 				.channel_power = 9000 - Value * 100,
 			},