new firmware update posted today one of the changes is increased voltage to 760 This is the fix you all are looking for so I suggest anyone with flaky performance on there C1's do this update. I pushed my voltage up to match the new update and my miner is running even better then it was a 745 volts
I updated a C1 this evening and it was easy - exactly like an S3. Download on a PC, connect to the C1, select the .gz file on the C1 web interface, transfer to the C1, then confirm the flash. I kept the settings (network, pool, etc.). It flashed but then hung the first time back. I cycled power (don't cycle power unless needed and not until the flash is complete) and the C1 booted normally and works well.
After the reboot, speeds were 250 and voltage was 0760.