So is it the last miner on the chain?
If so I would suspect cables.
But if it is one of the miners in the middle of the chain I would need to think about it.
What is the power brick 5 volts 2.5 amps
Or 5.1 volts 2.5 amps.
The official rasp pi brick used in the cana kit is 5.1 volts and 2.5 amps
one is middle of chain, i have another one acting similarly which is first in chain. I was able to watch one fail first hand, not sure if it is root problem or a symptom but the fan RPM went to 0, it continued hashing ( i am surprised it would still do this), exhaust temps continued to rise, PG start going down (I assume it was pulling power to reduce hash to in turn reduce heat), than the unit fails, after that it will start popping in and out of CGMiner until a physical power reboot. Weird thing is the fan runs fine after the reboot, makes me think maybe there is an issue with the module. I am surprised the unit doesn't instantly stop when the fan goes to 0. Still waiting on resolution from Canaan support.
edit - just to add, they say there is less than 1% failure rate with these units, I have been having issues with 3 so I must be extremely unlucky. My other ones have been running great however.
Under the listing it shows,"+5.1V 2.5A output" I haven't confirmed it my self