[Linphone-developers] Weird problem Linphone Android: Connectivity lost permanently

[IVAN FERNANDEZ]

Hi all,

I'd like to report a weird problem that we're observing in our linphone version for android. I'll try to explain it clearly hoping someone could give a solution...

The app:

Is a customized version of linphone based on 3.4.0 version for iPhone. The transport is set to TLS and "Only wifi" option is set to NO.

The problem:

At some point, the device lose signal completely (no data conection or even GSM) becoming a sad brick uncapable to receive or make calls. Closing Linphone doesn't has effect. The connectivity is only recovered by rebooting the device or (sometimes) turning on/off airplane mode. 

The problematic cases

We've observed this issue (at the moment) only in two combinations of device/carrier:

- Samsung Galaxy SII, carrier Vodafone

- Samsung Galaxy SIII Mini, carrier Vodafone

The issue doesn't appear in this other combinations:

- Nexus One, carrier Vodafone

- Samsung Galaxy SII, carrier NO Vodafone

- Samsung Galaxy Ace, carrier NO Vodafone

- HTC Hero, carrier NO Vodafone

The hint

In both problematic cases, we noticed that the connection type ALWAYS changes to "H+" for a seconds in both register and unregister (on exit) process, then the connection changes to 3G->H again. In the other cases, the not problematic ones, there's no change on connection type; if it's H it remains H, if it's 3G it remains 3G, etc...

We have found several posts reporting this kind of lost connectivity problem associated to the frequent switching between 3G/4G mode, particulary on Samsung devices, this one for example:

http://android.stackexchange.com/questions/24705/losing-connectivity-with-my-carrier-how-can-i-reconnect

so we think the origin of the problem is this forced change to H+ on Linphone register; when you are on an area with weak connectivity -> data connection come and go -> linphone tries to register each time the connectivity is recovered -> Linphone forces H+ change -> the changes makes the terminal lose the signal.

*******************

So... anyone has experimented similar case? Am I going mad? An important amount of terminal could be potencially affected by the issue so we think that looks quite critical.

Thanks in advanced

Best regards