Haven't seen this before and thought I would put it out there in case anyone can provide knowledge.
Whilst speed matching my locomotives this afternoon I noticed that I have one that goes a lot faster in reverse than in forward. Like, 2-3 times as fast. Naturally I first suspected something mechanical, but when I pulled out the decoder and swapped in a DC lightboard and tested on DC, the issue completely disappeared. I verified all this with a stopwatch. (And it's a Kato C44-9W but I think you'll agree that's irrelevant.)
The decoder is a slightly older Digitrax DN163K1B, the one with the 3mm LED that they replaced with the DN163K1B. Upon taking the shell off and doing some programming and testing, I had a couple failed read-backs in JMRI and then at one point the loco started moving and ended up off the end of the programming track. (i.e. not just the little jerk you often get each time a CV is entered). Upon further investigation I realized that I had failed to put any Kapton tape on this install like I usually do. I rectified that issue, put the loco back on the track, and it wouldn't respond to the command station at all anymore, even though on the programming track things were reading back fine. Eventually I reset the decoder (CV8). That got it to respond again on address 3, but ... the speed issue is still there.
Anybody run into this before? I suspect that one of the motor driver chips is shot, and that I should just replaced the decoder. But I thought I'd throw it up here in case anybody ever saw this before.
