Hi,
I’m reporting in with the same issues.
I have 40 P315s and most all of them seem to be doing this based on reports from staff. Some may not sit idle long enough. I can replicate the issue in my office. I haven’t had time to collect detailed logs yet. My pjsip timeout is 90 seconds and my sip keep alive interval configured in endpoint manager for my profile is set to 0.
Latest firmware 1.66.