Dga4132 keepalive or similar function


I have a big problem with this router / modem. There is a sort of 60 second time limit beyond which I can no longer receive incoming calls. Outgoing calls always work. Unfortunately I don't see any reference in the VoIP configuration file as keep alive or something that can work in the same way.

How is this related to OpenWrt?

Because the dga4132 has openwrt as os.

DGA4132 may be running a special OEM version of OpenWrt, but there is no official OpenWrt support available for this device AFAIK.

Ok is not officially supported but being based on openwrt, it would be useful to understand if in the official versions, there is something similar to the keepalive on the telephone part. The router is rooted so if there is any string I can add it would be useful.