Hello again folks:
Well, I have made some progress since my last post. I disconnected the decoder, the motor booster, and the interface cable; I shrink wrapped all their connectors and reinstalled everything one more time. I reset the decoder to the factory settings and tested the loco on the track.
The loco run going relatively fast but at the same speed in both forward and reverse. The sound is working perfectly well but in serial mode, and It is definitely a great sound. I guess some of the old LGB sound board will only work in serial mode (or it may be the 55030 that only work in serial mode). I am determined now to sort this thing out before change course.
I have since discovered that LGB of America recommended two 55021 for chipping this loco while LGB Germany recommended one 55021 and 55030. More to come!
Keith try sending the sound command in serial mode,