I recently installed a SDH104K decoder in a Kato Dash 9 unit and noticed at slow speeds, lower speed sets when the bell function is on and the horn is pressed the locomotive hesitates slightly. Is this normal with this decoder?
No, that is not normal at all, but indicates that perhaps your track voltage or amperage is too low. What DCC system are you using? How many track feeder wires do you have connected around the layout? What gauge of wire is your track bus? Much more detail is needed in order to determine where your problem lies.
MRC Prodigy Square DCC system with 12 gauge track bus wires and 20 gauge feeder wires at least every 2 to 3 feet. Note this only effects this Kato unit/sound decoder when the horn is pressed. my Other locos with Soundtraxx Tsunami decoders work fine.
Okay, it shouldn’t have anything to do with your DCC system or wiring. Try a factory default reset of the decoder and start over. Sometimes weird values are left in some of the CVs during testing.