To answer my own question for a Mitel 5000 CP system: In the Mitel DB Programming tool, enable "Online Monitor" under View (at this point it warns you about playing with things you shouldn't). Then navigate to System, Devices and Feature Codes, SIP Peers, SIP Phone Groups, the group that the phone is in, Configuration, Timers. You'll want to set "Default Registration Interval" and "Maximum Registration Interval" to something less than 3000 (the system default is 3600, I chose 2400, I believe they are 10ths of a second which gives me a 4 minutes re-registration time). You probably want to do that for all your SIP Phone Groups.  I'm trying it now, will report any success. ... View more

That indeed sounds like a reasonable diagnosis. My question:  Where do you change that?  Presumably in the Mitel system itself, not the phone?  If on the phone, do you know where?  The VOIP menu on my handset doesn't have anything but SIP login options.  The Mitel controller has a bunch of records for that handset that indeed have timeouts for 3600 seconds, but I can't change them. ... View more

Thought it was just me. We have a 5624 and it just falls off the network randomly - despite being on the Wifi and ping-able at all times and nothing showing unusual on the device / wifi, it sometimes suddenly decides that it can't connect to the server (i.e. the Mitel appliances... but they are up for literally everyone else for 100+ IP phones that are wired in).  IP traffic to it passes fine but it thinks it's not there. Turn off, turn on, it reconnects works absolutely fine again. We literally have it as one of the only devices in a room with a Meraki MR33 for most of the time and it only seems to do it when it's in that room - when it's roaming between points it appears to work just fine.  It's when it's sitting in the office, and is there for a long time, it decides to just fall off.  So it sounds sleep-related somehow. Very frustrating, given that there isn't another piece of kit on site that exhibits such symptoms and we are Meraki for all switching and wireless. We also have MR16 and MR18 devices, and most importantly it *never used to do that* - it didn't start at any given point (e.g. immediately after a firmware upgrade, or when we swapped to an MR33, etc.). ... View more