automatic pool cover oil

[kirstenv]

Hello,
We have an inground 32,000 gallon pool that our county requires automatic pool cover or fence surrounding. We chose the pool cover and have had issues from the beginning. The pool can be beautiful and clear but once the pool cover is on for a day and then removed there is an oily coating on the water and the clarity is gone for days. This only happens when we start to heat the pool for summer. The pool and cover company have tried changing the cover but the oil returns. They both say they have never seen anything like this. Is there anyone who has had a similiar experience or has heard of such a thing ? I would be forever grateful for any advice or ideas....anything. Thanks kirsten
ps. the pool is perfectly balanced before this occurs.