Sometimes I just see every few second in Plex Web message that someone started a playback, message will reappear every 5 sec:
8:14 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:13 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:12 PM User1 started playing Elementary - Bella on device.
8:11 PM User1 started playing Elementary - Bella on device.
8:11 PM User1 started playing Elementary - Bella on device.
Only solution is to refresh web but then again with time it's going to get nuts again.