Board freezes up

Hi.

I'm spending a lot of time buiding different versions of GCC on my Ci20.

Usually the board will freeze up fairly early on during the build. I will typically need to reboot the board three times, before I get a build which runs all the way through.

I have no idea what causes the problem - the board simply becomes unresponsive and I have to reboot/power cycle.

I have a high quality 2 amp power supply (Anker) with a USB cable designed for power rather than data. I've never seen the board draw more than 0.5 amps anyway, though.

This is with the latest stable Debian 8.

Connectivity is over ethernet (but the wifi has not been actually disabled). The SD card is being used as swap, but actually far as I can tell it's never used during a GCC build.