Modelrail 16xx - Rapido Trains

[MervynJSt0kes]

Recently received this model, and after running it in on 12volt DC, I found the motor to be very 'squeaky' at low speed after the DCC decoder was fitted. Loksound V5 Micro. Contacted Kernow MRC, who are supplying the models, and sent the loco back to them (obviously without the decoder !!. They supplied a replacement very quickly (excellent service), but I have the same issue with the replacement. Kernow ran the original at 12 volt DC, and as I found, it appears to be OK. The squeaking is appearing once a DCC decoder is fitted.
I have contacted Rapido, they have suggested it might be due to the rating of a voltage suppressor fitted to the main PCB in the loco. There have been other reports of problems that may be down to this suppressor. They are offering to send out modified PCBs that owners can fit themselves !!
Has anyone else had similar problems with this model, and resolved the issue themselves ? Any info gratefully received.
Mervyn Stokes