BLFs Graying Out/Disconnecting

[ShawnDev]

Regarding T48s:

I'm having a problem that I've been working on with 3CX. From time to time an extension or Parking space BLF will go gray and not be usable. The other BLFs continue to work so it is not a connectivity issue. 3CX looked at the pcap and responded thusly:

Quote:So on this time based on the screenshots with the BLF buttons for SP3, extension 304 and 303 the Subscribe buttons the phones send for all of these the Subscriptions and the PBX replies to all of them with " Expires: 900 " .
So this means that from the PBX point of view everything is ok.
Please provide this to Yealink and ask them since the PBX relies back the correct expiration time then why the phones do not update their timers ?

What can you tell me about this?

We are using 3CX 12.0.41311.996 SP.6.2

Firmware 35.73.0.40

I've also attached a screenshot of a phone.