I am not having troubles today and am keeping a tablet on and connected full time
David, I think I have read somewhere that with an iPad (dunno if you use that for tablet), already moving to another task in there lets you lose the connection in the fashion you describe.
For ideas it won't be bad to read through this :
A secure way to prevent Windows 10 , updates on the audio PC . Seems unrelated, but I recall that it contains useful info for when a NAS is used - all else the same as your situation, David.