Of course, you should always be sure there is sufficient airflow around a device. But ‘very hot’ isn’t enough to know if there is an issue or not. All electronics generate heat of some amount while working, it’s the nature of physics. If you’re concerned, submit a diagnostic and call the Sonos folks, I suspect that operating temperature is part of the data within the diagnostic. 
 

It’s possible, albeit unlikely, that the device is shutting down due to overheating, and then restarting the stream, but I suspect it’s much more likely that you’re having an issue with wifi interference of some type, and the CONNECT  is losing connection to your network. When a CONNECT loses the connection temporarily, it does exhibit the behavior you’re seeing, so again, I’d recommend that you submit a system diagnostic within 10 minutes of experiencing one of these ‘stoppages’ , and call Sonos Support to discuss it.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.

Thanks for the response.

It is certainly a lot hotter than i would expect and that it used to be, it’s only really the last few months have noticed it. It has plenty of airflow around the device. Although it’s in a rack there is more than it’s own height above it to the next shelf and nothing around it.

As for wifi, it is wired to the router as is the NAS.

will look up system diagnostics though.

It shouldn’t be getting hotter unless the vents are plugged. If it is there may be an internal power supply issue causing the heating.

I used a salvaged CPU heat sink on my ZP, cooled it down several degrees just sitting on a well cleaned top. Adding a bit of heatsink paste helped even more. Very similar to this one, don’t spend money on vapor tubes and the like as it never gets hot enough to see much good from them.

$15 bucks: https://smile.amazon.com/ARCTIC-Alpine-12-Passive-Silent/dp/B07CZZZ4DQ/ref=sr_1_6

I know my Connects run hot, though not so that I cannot rest my hand on top of them. And how hot it feels also changes according to the ambient temperature in the room - summers mean hotter feeling Connects.

All I have done is kept them on open shelves in rooms and there has never been a problem till now. Your location in the rack sounds fine to me - so long as ambient temperatures don’t run amuck as they seem to be doing these days in some parts of the world.