diff --git a/channels/chan_vpb.cc b/channels/chan_vpb.cc
index fe99d5df0b..cde5d483b9 100644
--- a/channels/chan_vpb.cc
+++ b/channels/chan_vpb.cc
@@ -372,6 +372,7 @@ static struct ast_channel_tech vpb_tech = {
 	.call = vpb_call,
 	.hangup = vpb_hangup,
 	.answer = vpb_answer,
+	.answer_with_stream_topology = NULL,
 	.read = vpb_read,
 	.read_stream = NULL,
 	.write = vpb_write,
@@ -406,6 +407,7 @@ static struct ast_channel_tech vpb_tech_indicate = {
 	.call = vpb_call,
 	.hangup = vpb_hangup,
 	.answer = vpb_answer,
+	.answer_with_stream_topology = NULL,
 	.read = vpb_read,
 	.read_stream = NULL,
 	.write = vpb_write,