Interrupted audio

We’re having a strange problem with our asterisk 13.4.0 server.

Somethimes the audio stream is interrupted. During troubleshooting we can see the stream is available at the ethernet ports (tcpdump is recording the stream), but asterisk won’t send the audio to the phones.

Also at the time this happens some of the monitored peers go “unreachable”. Seems asterisk “freezes” for a while.

Any thoughts about this?