Hi,

Voice output serial port is enabled on some Huawei models (e.g. E169) 
without problems, but for example on E173u-2 it is never enabled during 
an incoming call. There might also be other Huawei models having the 
same issue.

I traced the issue down to "^DDSETEX" AT command, which is used to 
notify the device to start streaming audio. It seems that Ofono sends 
this command too early on incoming calls. The command should always be 
sent *after* the dial "D" or answer "A" command. The patch fixes this 
behavior and afterwards voice will also work on E173u-2.

Bug: https://bugs.meego.com/show_bug.cgi?id=25004
Patch: https://bugs.meego.com/attachment.cgi?id=9702

-Jarkko