Lack of rtp

We have two ATA’s connected to an Asterisk conference bridge.
The one end stays connected for weeks, while the other one disconnects
all the time " for lack of RTP activity" ( see below)

Is there a way to tell Asterisk not to disconnect for lack of RTP Activity ?
I think one of the problems has something with the DSL connection

UIs there any help out there ??

[Dec 13 09:41:10] NOTICE[20848] chan_sip.c: Disconnecting call ‘SIP/204-000003c9’ for lack of RTP activity in 31 seconds


See sip.conf.sample

Or you could use Wireshark to see if RTP was really being transmitted from the remote side to the * server. Sometimes you can take these messages at face-value. It could be an issue with your firewall, blocking RTP back to the server. It could be a NAT issue. It could be a lot of things, but it’s always good to start with a packet capture.