Dropping calls

Having an issue losing the incoming audio, especially when on hold to toll free numbers. , other party can still hear. transfer to another extension and it comes back. Anyone have any ideas?
One more quick one, in the peer and user details of a trunk i have qualify=5000, is that correct or should it be qualify=yes
Thank you, thank you, thank you
I am using the latest versions of trixbox CE and FreePBX
__________________
John



Try
Try this:
http://www.trixbox.org/node/28002
Let me know if it helps.