While you wait for answers, we may have found some information which could help you.
Success
Message
How can I repair my phone?
How do i clear the TAM?
Fix blank screen in cordless hand set CLP99483?
BT 4600 twin one handset bot ringing?
TAM FULL on Binatone 1420 Single, base holds old messages th?
Mute?
How can i get my handset to speak with the caller?
How can I mend my BT4600 (1+1) phone?
Problem with handsets?
Bt 4600 phone?
Battery cover?
BT Studio 4500 cordless telephone?