I do recall when I first got the chime I was so excited and I hooked it up just to test it in my office. Needless to say it worked every time, notifications and mobile calling was solid for about 4weeks. Also, I had very little latency maybe 0.5-1sec after press - quite impressed. This was over WAN. LAN was almost real time.
Home renovation was completed and I installed it couple weeks ago when it decided not to work.
i recall two changes,
1. My director was on 3.2.1 and is now 3.3.3
2. I am now connected to a POE switch (unmanaged) whereby previously it was using a POE injector lump
im planning to test point 2 to see if POE is causing my problem. As said, intercom works just not with door bell.