Avaya 9408 Speaker Phone Button Fails

[DTGMI]

I have the following issue with a batch of 9408 OOS phones...

Any ideas?

A - All functions pass testing except when I press the speakerphone button I get a "beep" - Waveoff ... no normal speakerphone active response. ...

B - A good working 9408 tested on the same test digital port - the speakerphone button works properly.

C - Is there a way to factory default the 9408? I checked all the features and options - can't think of any tricks...

Thanks!