Silence when transfer to the phone with different codec

Asterisk Asterisk Support
1

Hello all.

I’ve noticed a problem:

  • Asterisk 1.6.2.19 (pretty old)
  • SIP phone with ALAW codec
  • SIP phone with G729a codec
  • SIP phone with G729a codec (one more)
  • no NAT

When dialing to each other everything works fine.
But when I dial from phone with one codec to the phone with another codec AND it transefers my call to another one (ALAW => G729a (OK) => G729a (problem!)), the remote party hears me, but I don’t hear anything.

I think it’s a bug of Asterisk (because when I just dial without transfers, everything works between phones with ALAW and G729a codec).

What is the best way to solve this problem? Does it appear in 1.8 and later releases?

Best regards, Alexey.

2

I don’t remember seeing this problem even with 1.6.x version and using true blind transfer REFER transfers. What sort of transfer are you doing?

3

david55, thank you for being ready to help, as usual!

I use attended transfer.

[general]
parkext => 700
parkpos => 701-720
context => parkedcalls
atxfernoanswertimeout = 15

[featuremap]
blindxfer => #9
atxfer => #

[applicationmap]

Transfer is done after picking up the phone by pressing # , then some other extension, then # once again and hanging up the phone.