Years ago I had a 
"Dodger" on my sailboat with clear vinyl windscreen and side curtains.   I always used automotive wax (Turtlewax..?) on the clear vinyl.  The dodger was 6 years old and had always been exposed to the sun. I never covered it.  The windows were starting to get 
Oh So slightly cloudy.  A friend had some stuff designed 
Specifically for cleaning vinyl windows.  He said 
Try This.  SO I did.  
 
Within three weeks the 
Oh So slightly cloudy windows had turned BROWN and you could no longer see through them.  At some point during this time period, I bumped into one of the windows and it actually "Shattered". 
 
I am 
Convinced that mixing the chemicals from prior applications the wax..and the chemicals in the spray bottle of vinyl cleaner had a really adverse reaction on the vinyl.  
 
LESSON: Beware of mixing 
Stuff.  
I think 
Armor-All has the same effect on car dashboards when mixed with 
Sun.