Callback - DTMF sending impossible last 2 weeks
 

I use Voxalot with Callback (Liv proxies the callback, calls are made using Voxalot)
Everything was ok for 6 months but on the last 2-3 weeks I find it impossible to send DTMF on callbacks mode.

I'd like to know whether or not anything has changes with Voxalot servers (I use US server), that could have caused this effect? or any idea to fix this??

I've already made sure nothing has changed with my Voip providers' servers & codecs, as well as Liv which proxies the callback)

Any idea?