I have roughly 30 of these phones in various client sites. My worst fears are coming true - these phones are failing at greater rates than ever. Grandstream has taught me some very important lessons. First - don't buy anything Grandstream no matter how tempting that low price is. Second - spend more time testing. Finally - If had spent more time viewing issues in Grandstreams own support forums and viewing their release notes for new firmware I probably would have not chosen to use these phones. The only thing I can do now is warn others of what issues they have to look forward to by using these phones.
The symptoms seem to be consistent with the ones that are failing.
These include:
1. Snap - Crackle - Pop sounds
2. Buzzing sounds
3. Decreasing volume - starts normal - but volume starts to go low to very low
4. Failing buttons - they stick or stop responding
Note: These phones work well in the beginning but over time they start acting up.
