it's like 2 years ago this posting, but I thought its worth mentioning.
we have bought many of this GXP2200 for our customers, and we now started to get complains about it. even one of them in our office has problems with sound, called party gets a very strange bass sound, sometimes both parties cannot hear each other.
also specially in our office, when a collegue calls me with the speaker instead of the horn, then I cannot hear hem, I hear something but is not understandable, it's like a broken bass speaker talking on the background.
I have contacted the Grandstream support, opened a ticked, hopefully they can solve the problem.
before this problem was only by using speaker for some customers. now it's also when you use it normally with the horn. so there is a problem in the software I guess. We have updated to te latest versions of the firmware, still no resolution.
We also found out that if we do factory reset, the phone functions good for the next 4-5 calls, after the reset, but then it starts same problem again.
for now we have decided to replace the phones by new out of the box and we did that, that solved the problems obviosly
, but this cannot go on,
they are not cheap, and it's not a game, to go to all complaining customers, change the phones. this cost too much.
if anybody had this problem, and has found a solution, please post it.