To clean it, take the cover off and you'll see the laser assembly near the spindle, with a lens on top - the assembly moves from the inside of the disc out on two small rails. Use a Q-tip with a little glass cleaner on it and VERY GENTLY wipe the lens in a circular pattern - it moves up/down within a coil, so be careful. Sometimes a little can of compressed air to dust off the area beforehand can be helpful.

While in there, also clean the disc contact area on the lower spindle - often rubber or felt - with the another Q-tip. It can get dirty and sometimes cause slippage.

If you're going to have to replace, a Blu-Ray player is almost what you need to purchase by default. My first choice would be Panasonic, but since models vary, check online reviews for a particular model.

I'm not aware of any Japanese manufacturer who actually manufactures Blu-Ray/DVD players in Japan anymore, and almost all of them are simply made by OEM manufacturers in China.

If money is no object, and video quality a priority, check out Oppo DVD players! :-)

Of course, if it was Windex, then that is already blue, if not, maybe just ink from production marking stamps around the lens assembly.

Please do update the results - layer changes have always caused a hiccup in DVD players but most newer players have really minimized, or even eliminated it.

One other thing to watch out for is fingerprints or smudges on the outer edge area of the disc.

DVDs, as well as CDs, read from the center of the disc to the outer edge, the reverse of what a record album does. Most dual layer DVDs are what's known as a RSDL (reverse spiral dual layer). They read the first layer from the center out to the edge, the player then re-focuses the laser up another .55 mm into the second layer, and are then read from the outer edge back to the center.

Fingerprints and smudges are common in this area from handling and can also cause skipping/layer change problems.