Problem with Freeduino Serial v2.0 board

The problem is that I can't reliably upload sketches. It's a little intermittent although short sketches (around 2k) usually work and longer sketches of around 10k usually don't.

I get the avrdude protocol error, expect=0x14, resp-0x51

Once an upload errors, even small sketches then fail to upload , and a new bootloader must be burned to cure the problem.

The problem occurs on two PCs tried, both running Windows XP sp2 connected using either a standard hardware serial port or USB to serial converter cable.

Both machines upload to a USB freeduino perfectly!

I can wire in a couple of 10uf caps back to back in series to make an NPO but I have seen nothing about the cap being a problem from anywhere other than the that thread. All the diagrams I have seen show the cap connected with the negative to ground.

I should probably just try two caps as an NPO if only to see if that cures my issue.