Hi Jerry I have only done measurments with ptime 80 and 100 and these are ok. One thing that caused me a lot of problems was that some of my phones was not able to produce frames fast enough when PJMEDIA_SND_DEFAULT_REC_LATENCY was 100 i.e. the old setting. I think Benny changed this to a higher value later on but I still have 200 on some old devices like HTC 3600 while more powerful devices like Motorola Symbol can handle 100. I have never played with the PJMEDIA_CODEC_MAX_SILENCE_PERIOD /Johan Jerry wrote: Hi all I am hoping someone could advise some of the optimal settings you have found to work well for windows mobile 6 and above. Reading through the mailing lists, I have found some people that have used the settings below, but would like if you could post the Values you have used and perhaps other settings apart from the ones below. #define PJMEDIA_SND_DEFAULT_REC_LATENCY = ? #define PJMEDIA_SND_DEFAULT_PLAY_LATENCY = ? PJMEDIA_CODEC_MAX_SILENCE_PERIOD = ? frame ptime = ?