Since all the hardware seems to have been replaced it is difficult to understand what might be going on.
If the errors do not seem to be initiated due to application usage patterns then if it were me would try defining a new profile with just your mount and a single camera. Dome, focuser, GPS and so on disconnected. A minimal setup to see if a stable system can be obtained at some point. Then build it back up slowly towards your present configuration working towards the focuser and dome last. See if the problems reappear with a particular device or some number of devices. Testing each configuration to the extent possible. Its a pain but could perhaps expose another viewpoint.