Very strange problem but when i try to download a sound file from and engine it works for about the first 10 to 15 percent then i get a checksum error and the engine takes off in forward. This happens on multiple engines and i am using a usb to serial port connector if that matters. Does Any one have any ideas?

Not much help but take a look. It seems you're not the first.

http://ogaugerr.infopop.cc/eve...=220105352#220105352

I've never experienced this, however, I suggest trying the following:
• First, remove everything from the output of Fixed #1 and replace it with a short piece of track, preferably with a bumper at one end.
• Place the engine on that track and follow the Loader Program's on-screen instructions to download (actually, upload) the engine's sound file to the PC.

If the problem recurs, try using a different TIU channel, making sure to keep the keep the TIU powered either via Fixed 1 In or Aux. Power. Also, place the Variable channels into Fixed Mode before attempting to use them.

i am using a short peice of track two sections actually. i am also using fixed #1. i havent tried a bumper but why that make a difference mine dont do anything with the track circuit.

The bumper is because you stated that "the engine takes off in forward".

If this happens on all of your engines the problem is most likely the TIU or the PC setup.

As I stated above:

"If the problem recurs, try using a different TIU channel, making sure to keep the keep the TIU powered either via Fixed 1 In or Aux. Power. Also, place the Variable channels into Fixed Mode before attempting to use them."