I think this is related
http://forum.voxalot.com/voxalot-sup...way-audio.html
I was having same problem. Couldn't solve it, but got around it by getting VoXalot to forward to a my main provider which I had registered in PAP2 instead of registering directly to VoXalot. Incoming was suffering only, not outgoing.
These guys also report similar problem intermittently
http://forum.voxalot.com/voxalot-sup...-provider.html