[Asterisk-Users] "powered" analog phone and adit 600 feedback problem

[Paul Zimm]

I'm using an adit 600 channel bank with some "powered" analog phones 
that have caller id features,
and some "unpowered" analog phones. The "unpowered" phones sound great, 
but the "powered"
phones have a problem with loud feedback if you speak to close to the 
handset mic.

I've determined that its not the settings in asterisk or the digium 
cards by disconnecting the T1 line
from adit 600 to asterisk box.  I turned the gain down as far as I 
could. Any ideas?

Some adit settings:

pbz-cbank1> show 2:5
SLOT 2:
Settings for FXS:   channel  5:
    Type:            VOICE
    Signaling:       LS
    RxGain:          -9    dB
    TxGain:          -9    dB
    LineLength:      SHORT

pbz-cbank1> status 2:5

FXS    Rx AB  Tx AB  Signal=>T1 Sig  T1                 TP
---    -----  -----  --------------  -----------------  --
2:5      01     01      LS => LS     Traffic             N