HO F7 DCC with Sound running intermittently

[Peewogg]

I have a Bachmann DCC F7A with Factory installed sound value.
I have had the loco for about a year and it has run fine but recently it will start and stop randomly.
There is no apparent spot on the tracks where it happens and the time between varies but it does it consistently. I cleaned the tracks and wheels. It will sit for  10 to 20 seconds then restart on its own. If I turn power all the way down and then up immediately the loco starts moving immediately.
Do I need to reset the decoder? Any suggestions appreciated. Thanks.

[Hunt]

Remove locomotive shell. Locate, pull off and reseat one at a time the black plastic clip holding in place each of the two wires connecting the motor to the circuit board. Be sure the bare end of the wire is in good contact with the solder pad on the circuit board before replacing the clip. Best to solder the wire to the solder pad than using the plastic clips.

Test run before replacing the shell.

Also, clean the back of all six wheels and check the electrical pickups contact to the back of each wheel.  The pickups may need to be adjusted.

Place one drop of Conductive Contact Lube on each wheel tread and back of wheels.