Polycom 501/601s MWI randomly lighting up

On 3.1.3 with our Polycom 501 & 601 phones because that is the latest that Fonality supports. But there is one issue remaining: when users don’t have any voicemail, MWI and the message icon still randomly lights up for two minutes several times before disappearing again.

Disabled the phone’s voicemail and the phones are still randomly flashing once or twice during the day.

You probably want to talk to Fonality about that, but I’d look at packet captures to see if the phones are being told to turn on the MWI. If the capture shows a NOTIFY to the phone that says MWI should be on, then the phone’s doing what it’s been told to do. If it’s turning on without such notification, then the phone’s acting improperly.