[Nexus 4 Q&A, Help & Troubleshooting] ryuker:
I posted this in the PIAF thread since I used that method but this will help you guys as well.

Nexus 4 SIP echo fix - It's pretty bad for many users but this solved it 100% for me

It worked for me and I tested numerous different setting and configurations along with measuring my latency to ensure it works. YMMV but it's easy to try. At first I thought it was a Latency issue since echo didn't occur over

wifi

but with ping times lower than 60ms I still got echo over 3g without this method.

I'm using the silk codec(Silk 24 wifi/Silk 12 or 16 over 3g/4g); YMMV with other codecs.

*Before starting*

Root your phone, flash radio .27 or .33 if your on T-mobile or in Canada:

We want to enable Nexus 4g

! 3g is usually fine but 4g tends to have significantly lower latency(3G: 50-70ms versus 4g: 20-40ms). Sometimes my 3g speed was fine but latency sucks(100-250+ms)....3g has enough speed for VoIP but any latency issues/spikes/jumps will ruin a call.

This is a good guide to follow: Hippowise"s guide

For the first few steps plus a audio fix some users encountered with the radio downgrade; there are 2 scripts you can run via any terminal emulator app scripter(I used this $Scripter). The actual Script to be run can be found on XDA in the nexus 4 LTE thread(download or save them as txt files). The XML file I suggest editing your self(I just replaced all instances of epc.t-mobile with fast.t-mobile for T-mo users).

If said "scripting...wut?" just follow Hippowise's guide to the tee. Scripting is just faster/easier.

It took a few days for my 4g/LTE to kick in so be patient; It's worth the trouble!

**Now to the guide**

First, get the Faux kernel for Nexus 4 or use another kernel that has applied his patch.

2nd, get his apps from the Play store(they cost money but worth it): Faux Speakers and Faux Sound: Configure them for "voice" and "quality" respectively(you can adjust on your own from there, I upped the gain a bit).

3rd, Use Csipsimple and enable "Software volume control" instead of the default android/os/hardware based volume/gain control. I wonder if this bypasses Faux and puts volume control solely in the hands of Csipsimple. I would do 1-3 steps anyway because it fixes the SQ issues in general with the nexus 4.

4th. Enable Echo cancellation; until I did the previous steps, echo cancelation didn't work at all: YMMV.

I choose Echo mode Webrtc becuase Speex echo cancellation didn't work for me. If your codecs are different the other choices or auto might work better. Experiement.

5th: *Optional*

Noise Cancelation: Worked so-so....didn't need so I turned off

Voice Detection: I didn't like it but experiement.

Compact SIP packets: I use it, optional

STUN: I turned it on, I don't think it will hurt.

Audio troubleshooting in the Csip menu has tons of options to mess with. If all else fails, read some guides and experiment. I didn't need to chance anything here but some of it looks promising and has some fixes for specific models like the galaxy.

7th: Latency

Get Speedtest app from the play store and test your speed. In some areas over 3g I would get decent down/up speeds but godawful latency (300ms+ :eek: ). If your 3g latency consistently sucks, do the 4g fix for the nexus; Much better latency and I always get 4g in most places on T-mobile.....rural areas might be screwed on getting 4g although I noticed my 3g speeds increased overall after the fix.

8th

Finished; report back in the thread and tell me if it helped!! And if anybody knows a good I.T. position open for a VoIP office/callcenter; let me know cause I'm quitting mine. ;)