I often avoid audio questions as they are not a thing I can test and work on with the equipment on hand, so avoid it!
But this might be a time to look at the parts drawings to locate what parts on on the specific RV you have?
Step one will be to know specidific year, model and even down to the serial number of the RV, as there are two different build dates and the sat rcvr seems to vary with the different build dates.
If your serial number has a 7th digit of 1, it is early with a 2 being later build so maybe check that before beginning the as the rcvr location does change.
Start here:
https://catalog3d.winnebagoind.com/menu/Parts.htm
Sort to correct RV and build
Go to audio and then front end wiring!
Once down to the correct RV, there will be a list at right to ID the parts and numbers. On that list you can click an item repeated to make it flash in yellow on the drawings.
Bottom left corner is a symbol like a + to click before zooming and that lets you set a point to stay centered in the view. Scroll to zoom, drag to move the drawing around.
Bottom right to choose which overall view to start, front,back, top, etc.
It takes some play to sort the controls but nice as it does show the items in very much correct shape, size, etc, even down to mounting holes in many cases.
Handy if you need to take a dash apart?
View with two different locations shown, depending on build date?