The issue when we designed this system, (which hasn't gone away), is that apart from the RPi 3. which consumes up to 5-6 W during normal operation, we have two Audio Amplifiers that provide up to 12 W each. We wanted to provide a thermal path through the wall of the equipment case without compromising its water and humidity resistance. Plastic IP65 cases provide the environmental integrity, but not the thermal performance. Metal IP65 cases are quite expensive, so we bought the Ammo box as a good substitute.Penri wrote: ↑24/05/2018, 13:38Sounds promising but I'm left wondering is you are struggling to solve an issue being exacerbated by the enclosure being used. If there's no good reason to keep the box and we can identify a suitable and if it helps more spacious box, whether it would be better to take the plunge and buy one.
Whatever kind of case we bought, there would need to be a good circulation of air over the chips on the Pi to prevent the kind of overheating that we are experiencing. The history of the development of this system is strewn with compromises. We were originally going to use a Pi Zero for spares compatibility with the Railway system, but at the time, I was trying to get the two audio channels to work through two USB sockets (the Zero has no audio jack). The trouble is that the Zero only has one USB socket and it needed a better USB hub at a cost of around £35 so we bought a Pi 3 instead. But the RPi 3 runs hotter and is (I believe) susceptible to overheating of the chip on it's underside.
That was why I fitted the original fan, the replacement for which is noisy...