OBItalk used on a protel modem for programming payphones

[Bob1]

I have a Obi 200 and use it to program payphones threw a Protel modem witch is compatible
 to a Hays modem. it works some time on some models. The problem I am experiencing is packet loss and data loss and modem dropping out. I have read changing Codecs-ITU G.711 May Help and making it priority. I would like to know how to do this and if their is more I can do to improve my device.
Thank You for any assistance in advance.
Bob Statler

[drgeoff]

Please do not post the same question more than once.

The default codec is already G.711.  That is the standard u-Law or A-Law telephony codec used on telco trunks.

You did not say which Internet Telephony Service Provider you are using.  That could be relevant.

[Bob1]

Google Voice is what I am using my Obi 2000 with any work around to get better results from my modem