JP1 Remotes

First a little history. I had an extended 9910 working great for quite a while, then a new TV necessitated some reprogramming. My old JP-1 cable seemed to be damaged, I kept getting the "Low SDA error" so I figured my cable was bad.
I purchased a new JP-1 cable from Tommy Tyler, made sure I had the latest driver and now
When downloading from the remote I get the warning "bad checksum at address $0000. Expected $4C $B3, but found $5C $A3"
When uploading to the remote I get the error "Data readback differs from data written"
The remote gets some of the upload, some functions still work and the time is correct, BUT the device keys don't work, or only partially work, and it seems that the remote still thinks it's in programming mode (after a few seconds it times out and says "exit setup"
Maybe I'm missing something, or maybe the cable is bad?
I'm just looking for some ideas, and I have NONE

Classic symptoms of low batteries. Also, the latest driver doesn't seem to work as well for most people as the previous version HERE.

Chris,

Keep me in the loop on your problem, particularly if you feel the interface may be faulty.

Tommy

Zellarman,

I assume we're talking about the USB cable not paraller, correct? If yes,

What sort of computer is it? Make, model, processor speed, operating system, single processor or dual, hyperthreading or not, USB1 or USB2?

Do you see many, many files such as these (written during the few seconds before the failure announcement)
$$DEBUG$$20080406.txt
$$DEBUG$$20080407.txt
$$DEBUG$$20080501.txt
$$DEBUG$$20080502.txt
in the IR directory?

And do you sometimes, right after the checksum error, see an error 'DevType15 4095 is not currently assigned...'?