What you might be experiencing is corruption of your DCC bus signals. These little devices are designed to fit as a pair to the ends of your DCC bus. You don't need more that two regardless of how big your layout is.
DCC Concepts DCC-BSS.2 Bus Spike Suppressors (2 Pack)
DCC Concepts DCC-BSS-2 Bus Spike Suppressor (2 Pack)
DCC / Layout Concepts DCC-BSS.2 Bus Spike Suppressors & Terminators Pack Of 2
Layout Concepts DCC-BSS.2 Bus Spike Suppressors & Terminators Pack Of 2
DCC Concepts DCC-Tag25 Power Bus Tag Strips (25)
DCC Concepts DCC-TAG25 Power Bus Tag Strips (25)
