Update
Today I went out and tested the temperature on the Surge Guard Transfer Switch when not plugged into shore power and it read 65 deg. F.
I then tried to clean the switch contacts again.
I plugged into 15 amp shore power (house) and tested the temp after 10 min. and it was still at 65 deg.
Following the test I wrapped the switch box housing in sound dampening foam (Amazon) and also added sound dampening wall foam that I've used in my music studio.
The result was a reduced volume level on the "hum" that hopefully is enough to allow us to sleep at night.
I see two problems:
1) Fleetwood should never have installed the Transfer Switch in a bedroom or anywhere in the living area if there is potential for Hum from a 60 hz switch.
2) The Surge Guard 40250 Transfer Switch is a poor performing product, just discontinued and has not been backed by the manufacturer.
I will probably end up replacing it, and it will not be with another TRS product.
Any recommendations will be appreciated.
Thanks to all that have provided input.