I recently bought a Atlas VO-1000 and a drop in decoder. I ran the loco first for a bit on DC and it performed great. Had slow speeds and was quiet. I took apart the loco and installed the decoder per the included instructions. The loco does work on DCC now but has issues. I have to turn the throttle up quite a bit to get it to move, I can then throttle down some and it stays going slower. There is also a zipping sound made when it is in motion. I'm pretty sure there is something I've done wrong on re assembly but cannot figure it out. I've took it apart and inspected everything several times to try and see where the issue is. Each time I reassemble I cannot clear the no slow speed start or the ziping noise. On the plus side this thing has stellar electrical pickup. Hasn't stopped once at all due to dirty wheels or track.