is there a way to reset the sound in a ho EMD GP40 (dcc sound) loco ?

[mr g]

I have this loco it runs, lights work according to direction. The only thing is the sound quit.
I am wondering if there is a CV that would reset the sound, or do i have to send it to repair
It is a BACHMANN item NO. 66310 HO EMD GP40 (DCC SOUND) READING #3675.
 Any help would be good Thank You

[Yard Master]

Hi Mr. G,

You can try a factory reset by setting CV8 to 8.

[trainman203]

Cv 128 is the master volume.  Reset to a value 100 to see if it comes on, then turn it up or down to suit.  But don't turn up so high the horn distorts.