Camera Live view randomly dropping

I have 5 floodlight cams, a doorbell and a spotlight cam. All are connected with good WiFi and have worked without issue for over a year. Recently, I’ve started having real problems with live view failing. Randomly. A camera is unable to show live video, but is recording video fine. A reboot always resolves the issue. This happens randomly on the floodlight cameras and I only find out when I try to look as I still get alerts from them get movement etc.  The devices are all connected to an enterprise grade network (Unifi Access Points, Unifi Poe switch, opnsense firewall) with the cameras all in their own vlan with all necessary port ranges available.  Can anyone offer any ideas before I contact support?