[Asterisk-Users] volume "fading in and out"

[Asterisk]

I've had several users today inform me that whilst they were on a call, 
the volume kept fading in and out to such an extent that they thought 
the caller had hung up.

I would dismiss this if it were a single person mentioning it, but it 
isn't ..

Has anyone else seen anything like this ? We haven't, and we've been 
running for nearly a year ...

CVS head as of 3 days ago, TE410p ISDN32 EuroISDN

Julian.