Strange. Just done a factory reset on Nexus 7. Wanted to copy some files to a USB stick so attached my OTG cable at which point Nexus switched off with no warning and refused to switch back on until I attached a power lead, whereupon it rebooted. It still had 90% battery life. Tried attaching OTG cable again and same thing happened. Have used the OTG cable in the past so don't think it's causing the problem. Any other ideas welcome. I could email myself the files I need but would prefer to be able to connect USB to Nexus.
Thanks to all in advance