Call drop

[ho.peter]

I use two 1750 router to transfer the voip at 128K lease line. But sometimes the call drop suddenly during the conversation. The connection like this:

PBX---1750 FXS----- WAN ------ 1750 E&M ----- PBX

The IOS is 12.1(5)T8.

Anyone have some idea? Which parameters will relative to it?

Thanks

[k.poplitz]

This might save you a call to tac: http://www.cisco.com/warp/public/788/voip/voip_debugcalls.html