Recently replaced an NEC8100 with a Mitel 5000 using digital 8528 phones.
A hand full of them are getting very poor voice quality when using the speaker phone. It is perfectly fine when using the handset but a ton of static and weak volume whenever they use speaker phone. I have tried replacing the phone and it didn't help and the phone I swapped out works fine on our demo system.
I should also mention that I checked the phone right at the phone system with the idea of eliminating the wiring and still the bad speaker phone.
Any ideas?