gfx glitches (2-slot neo)

I've recently bought a 2-slot neo geo mvs cabinet. It works ok overall but there are some gfx glitches. For instance, in puzzle bobble there are glitches about an inch to the right of some of the stars in the title screen. These glitches look like a few blinking pixels in the same color as the star that they are next to. Super Sidekicks shows a similar problem, white pixels appearing to the right of the lines which make up the playfield.

I've tried cleaning the slots and carts but no change.

There are two odd things about this problem: a) The problem gets less severe when the machine has been on for a while. b) If I only insert one game the problem basically disappears (and it doesn't matter which slot I insert it to).

Any help would be greatly appreciated.

The slots and cart contacts must be squeeky clean.
<a href="http://www.hardmvs.com/html/cleaning.htm" target="_blank">http://www.hardmvs.com/html/cleaning.htm</a>

Also check the 5 volts on the edge connect, should be just above. 5.2 volts would be OK.
If lower it can cause various problems.

I read that cleaning guide already before I cleaned the slots and carts.

The 5 volts line measured 5.16 which seems ok. But after adjusting it to around 5.04 the glitches appear to be gone.

I've tested it for a while and there don't seem to be any new problems after lowering the voltage. But I need to test it more before I can be sure ofcourse.

Thanks!

As a rule, tiwnkles iunthe sprites would be the fast RAM located WITHIN either Neo-C0 or Neo-B1. Those chips are hard to come by. I would live with it, personally. My Don Doko Don does the same thing, but htere is no way I can get anything for thaqt one...