No only randomly in general play and at the very end when credits come up. Will be checking connectors J101 and J114 again (upgrade maybe) and then perhaps move onto caps bridge rectifiers. ( not looking forward to that!) All components on driver board are original so perhaps it time for replacements. Thanks heaps for the help. Open for any other suggestions.

Reseating those connectors may improve the stability on the short term, but will also prove that they are the issue. Much easier to replace the connectors than replace the BR and Caps !

Do you have any mods in the game ? They can tip the +12V or +5V into a random reset.