Bill--See this link concerning the ES mirror situation. Don't be afraid to open it up. The circuit boart just plugs in like a computer sound card. You can't hurt anything. Study the affected area and see how it works. You'll undoubtedly conclude your own remedy procedure. Remember, just because you fixed it when the weather is hot doesn't necessarily mean you've fixed the problem for all times. But you can sure cut down the frequency of the problem.
http://www.instructables.com/id/How-...e-Lubrication/