Why does background crash when receiving dtmf via rfc2833?

Question

Asterisk

Good afternoon! Please tell me what could be the reason. When you press the buttons in ivr, the background falls in asterisk, dtmf is set to rfc2833, while it falls when you press any button on the phone.
there are codecs ulaw, alaw, gsm.
Asterisk 13.38.3

Writes like this in the logs.

-- Executing [[email protected]:2] BackGround("Local/[email protected];2", "ivr/hello") in new stack
-- Playing 'ivr/hello.alaw' (language 'en')
tver -gw*CLI>
Disconnected from Asterisk server
Asterisk cleanly ending (0).