Quoted from ChrisHibler:

First, run display test as mschonbrun suggests, above.
Second, if you have another WPC game (not WPC-95), swap DMD controllers to see if the problem follows. You can't damage the game doing this.
If the problem follows the board, there are two filter caps on the board that are 150uf/160V. Replace them with the more common 220uf/160V caps. It's a pretty easy replacement if you have any skills at all...and a decent iron.
--
Chris Hibler - CARGPB #31
http://www.ChrisHiblerPinball.com/Contact
http://www.PinWiki.com - The Place to go for Pinball Repair Info

Quoted from schudel5:

Yes.

Then the DMD is bad (unlikely causing this issue).

That's a controller/HV board issue and not a DMD issue. You can swap the DMD driver board from HS2 into FT and I'll pretty much guarantee FT will have the issue.

Quoted from PinballManiac40:

I doubt reseating this ribbon cable will help but try it anyway. It is a source of many animation issues that are not voltage related.

Quoted from Hawk007:

As Chris says...95% its the 2 large axial caps on the HV dmd controller board. . Either way they are old and need to be replaced anyways.
Easy to swap out with a temp controlled solder iron.

Quoted from schudel5:

Not sure if you meant that you can't find them on the board or that you can't find them for sale. Anyways, here's the location for both.
https://www.greatplainselectronics.com/proddetail.asp?prod=CEA-220uF-160V-RMD