My first thought was also a dirty stylus.
The stylus can get dirty it two ways.
- Simple dust and lint can accumulate on the stylus and actually lift it up partly out of the groove. This can usually be seen by a close look. I use a simply natural fiber soft artist brush to wipe the stylus off.
One must be careful though. You don't want to bend the cantilever, the small arm the stylus is mounted in. Best to use only forward movement on the brush, and definitely minimize side-to-side movement.
- Next is the accumulation of pure crud on the stylus. To see this, you need to look very very close, frequently with a magnifying glass or small microscope. This crud is like a fine cement caked to the needle.
The best way to clean this is with a Mr. Clean Magic Eraser. This is an ultra-fine scrubbing pad, available in most grocery stores. Set the stylus down on the dry pad a few times and it will rub all the crud off with no damage to the stylus. But once again, the Stylus must move straight up and down on the pad, no side-to-side or front-to-back movement. Side or front movement runs the very real chance of damaging the cantilever. It doesn't take any pressure beyond the simple weight of the cartridge to scrub the stylus clean.
This is not something you want to do frequently; two or three times a year is typically more than enough.
To clean my records before play, I clean them with a microfiber cloth that has been moistened with a fine mist of some home made record cleaner. In my case, it is distilled water with a couple drops of isopropyl alcohol, and a couple drops of some old Radio Shack record cleaner I had laying around. This is in about a 3 or 4 ounce spray bottle. So the amount of alcohol is very very very diluted. It simply gives a very mild solvent quality to the distilled water. The Alcohol is optional, one could use a fine mist of common distilled water, just a light mist to make the dust cling to the cloth.
When you look at cleaning fluids, you need to make a distinction between Record Cleaning, meaning cleaning before play, and Record Washing, which literally means washing the record. Both are typically referred to as 'Record Cleaning Solvents', but the record washing is much more powerful, and more likely to leave a film.
There are also Stylus cleaning fluids that typically come with a special stylus cleaning brush. These tend to not be cheap though. But on the other hand, a tiny bottle will last for many years.
Just a few thoughts.
Steve/bluewizard