Thanks. I will check that. I may just pull off the speakers too and see if they are damaged/split. The volume does seem kind of loud.
Is the noise really coming from the shell or from the speaker because you have the volume too loud? The sound will distort in a small speaker if you have it set to max volume. Try turning the volume down and see if that doesn't improve the sound. This is done by progrmming the master volume CV. Read through the QSI documentation that came with the loco to find the appropriate CV number and range to which the vollume can be set. I think 15 is max volume on QSI. P2K locos usually come from the factory with the volume set to max, which is usually way too loud and distorted.
I see some other posts here about Proto 2000 E7s. Maybe I'll ask my question in this forum first.
I have a P2K with factory QSI sound, but the shell vibrates with the speaker volume. Nothing is really loose on either the shell or the electronics or loco body, just that the tightly-fit shell starts to buzz noticeable with sound on. It's not acceptable as is.
I imagine it is particular to these long bodied locos and the casual fit method of the P2K with just two little tabs in the middle of the frame and slots on the shell to fit together. I think it is the whole shell just vibrating along the long flat metal body sides. When I simply squeeze the shell with my fingers I can stop the buzz.
Any suggestions? I could put in some glue or cement of some kind or double sided tape along the metal body, but it might prove permanent even though I use caulk or tape because of the tight fit and lots of flat metal to shell contact. What do you think?