noise while making a phone call: hardware or software?

[Michael Shiloh]

As we all know, during a call with GTA01 noise is heard in the speaker. 
I know this has been discussed in the past and I thought someone had 
found a soft way to solve this. One of the settings in the mixer was too 
high or something like that.

I've been searching for this item but all I can find is bug # 883, which 
says it's a hardware issue, interference making its way into the GSM 
audio path one way or another.

Does anyone recall any software explanation for this?

Michael