No audio from Android <> Softphone

[Snomon]

No audio from Android <> Softphone

- I am running 12.5RC with latest android and windows softphone.
- Both devices off Local network. Softphone at home office.
- Softphone can call extensions at main office fine.
- PBX Delivers Audio is OFF
- Android is a Samsung S5
- Not using tunnel. Presence screen is showing up correctly.
- This post is submitted under the android forum because my iPhone 3CX app audio works fine with the softphone in question.

If my android is on the home office LAN (same subnet as the softphone) my android (which is at different extension) can call the softphone, but no audio either direction. The android can call extensions at the office and the audio is fine.

When I turn off WIFI on the android and switch to 4GLTE, same results no audio either direction. My softphone can still call extensions at the office no issues.

The following tests are interesting:
- On either the android or the softphone, if I hit the REC button, the audio works both ways!
- If I let it go to voicemail the recording is actually there with audio ok.
- If I toggle "record all calls" on the server for either the android or the softphone, it works fine.
- If hit the checkbox on the server for PBX delivers audio for EITHER the android or the softphone, it works fine. I trying to make this work with this option OFF because the audio is better.
- If I turn on the tunnel it works.

Anybody else experience this? I guess I'll leave the TUNNEL for further testing now as I am still able to get presence / chat to work thru the tunnel.

 

[leejor]

Are you by chance, using the same local port (5060) on both the Windows and Android phone. That could cause issues when both devices are "viewed" by the PBX from outside the LAN, and could cause port forwarding issues (confusion) with your router.

 

[Snomon]

Are you by chance, using the same local port (5060) on both the Windows and Android phone. That could cause issues when both devices are "viewed" by the PBX from outside the LAN, and could cause port forwarding issues (confusion) with your router.

Yes I'm using same 5060 port. I thought this was the culprit until my 3CX iPhone app (installed on an iPad even) at home on my home LAN (same as the 3CX softphone) and I am able to call with audio both ways. It's strange how hitting the record button on either android or smartphone lets the audio through!

Also in regards to same IP/5060 port, I disconnected my droid from WIFI/Home Lan and went back to public 3G IP address. Still no audio (only to softphones!) unless I turned tunnel on.

 

[leejor]

I disconnected my droid from WIFI/Home Lan and went back to public 3G IP address. Still no audio (only to softphones!) unless I turned tunnel on.

Do you get audio, on the softphone, on a call from an extension at the 3CX server site, when this happens?

 

[Snomon]

I disconnected my droid from WIFI/Home Lan and went back to public 3G IP address. Still no audio (only to softphones!) unless I turned tunnel on.

Do you get audio, on the softphone, on a call from an extension at the 3CX server site, when this happens?

Yes softphone to extension at server site is OK. And my softphone isn't using the tunnel. Strange.

 

[leejor]

Yes softphone to extension at server site is OK. And my softphone isn't using the tunnel. Strange.

But what about a call the other direction, that is the real test that the router at the remote end is able to direct the voice packets to the correct device.

 

[Vali_3CX]

Hi

To me, according to your detailed feedback, everything points to a RTP port mismatch between the two phones. Let me explain:

- when you don't use tunnel, you don't record call, the PBX don't "record all calls", or PBX don't "deliver audio", in these cases the audio "channel" is a direct one between the phones, A<->B.
- when you use tunnel, you record call, PBX record all calls, or PBX "deliver audio", in these cases the audio channel is "intercepted" by the PBX, ie A<->PBX<->B.

While "PBX delivers audio" is provided to ensure, by audio transcoding, maximum compatibility between the codecs of the two phones, the tunnel is provided to avoid, by multiplexing, RTP (audio) port mismatches between the two phones.
So, bottom line, my opinion is that the Android phone is not properly STUN configured or stun is not active.

Now, from my experience, there is a trap (in which I fall myself several times) which happen when the PBX has the same address for both In-office/Out-of-office or both these addresses are reachable from "out-of-office": the softphone first time attempts to connect IN-office - so, in our case, it succeeds. But, in fact, you're Out-of-office. The difference between the In- and Out-of-office is the STUN: it is activated ONLY for out-of-office (and 3G is, should be, always out-of office). The STUN is the one who ensure proper port matching when "out-of office" (and messes them when in-office).

So, after this long explanation, it worth to have a look at Android's connection icon: if you're on 3G, it should show "the house", not "the building"...

Hope it helps a bit
vali

 

[botika]

I have the same problem when calling to mizudroid. However mizudroid seems to work with other softphones well. Except 3cx.
Please have a look when you have time.