Maynuo M8811 restart problem?

[JMcC]

I have a Maynuo M8811 that has an annoying problem when communicating with a PC. After a while of normal running (reading current & DVM, the PSU resets for no particular reason. This happens with both the official software & a labview program that I wrote for it.

When not communicating with the computer it works fine. Baud rate is 38400, though it also happens at 9600. There is no set time for the reset to happen. Sometimes it runs for >30 minutes, sometimes less. The load currents are quite small (< 10mA).

Anyone seen this before? I'd like to be able to record long term using this unit.

Thanks,

JMcC

[mcinque]

since you say it happens only when connected to the USB, it would be useful to see if there is any correlation between the reset and some particular USB data. Can you hook up a logic analyzer and trigger the USB dump around the moment the PSU resets (i.e. when the voltage is cut out by the reset)?