Gosh KC I think someone swapped parts or tenders on you. Can you post a photo of the circuit board?
I grew up with MPC and still love the trains from that era. The 8600 was a large 2046-type Hudson that headed up the Empire State Express set in 1976. It re-introduced Magne-Traction after an 8-year absence, but it didn't have a whistle from the factory. (Lionel discontinued the whistle after problems with it in the smaller 8206 Hudson, which was their top-of-the line engine thru 1975.)
IMO the original Electronic Mighty Sound of Steam without whistle sounded pretty good. At least it was clean and crisp. It was also properly synchronized to the driving wheels and puffing smoke. When Lionel reintroduced the electronic whistle in the 1980 Berkshires, the steam sound got muddy, and the precise synch was lost because the chuff was modulated by a Hall-effect sensor on the tender axle.
Look for a Sound of Steam tender from an 8141, 8203, 8303, or 8304 at a local swap meet. Put down a fresh layer of foam or double-sided tape and give it a try. You might be pleasantly surprised!