[Asterisk-Users] strange sound when bridging Zap

[Andrew Kohlsmith]

T100P with an Adit600 channel bank.  16FXS, 8FXO.  Been doing this with the 
past month or so's worth of CVS HEAD, probably longer.

I have a weird problem when I bridge calls...  not always but often enough to 
be nasty.  Call comes in FXO, * calls my home via IAX2... times out so picks 
up another FXO port and dials my cell.  7 times out of 10 it bridges just 
fine, but about 30% of the time I will answer and whenever I talk on the cell 
I get back a "buzz" (almost sounds like an overdriven dialtone) for the 
length of time I talk.

e.g. if I say "Hello?" I hear that overdriven dialtone back at me about 0.5s 
later for the duration that it takes me to say "Hello?"  The louder I speak 
the louder the return "buzz".

Nothing unusual in the log (I get the odd "unusual state 6" message but it 
doesn't seem to be related)

Any ideas?

Regards,
Andrew