It does become all a bit technical.
Essentially the DVD1 has some inherrient design flaws with its mech. This was why it was eventually upgraded to a more reliable mechanism.
The DVD1 mark 1 mech can internally overheat. Causing component fatigue after a period of time. This is not uncommon for any manufacturer of PCBs - especially when used in intstances or machines they werent designed for.
In theory, it could be fixed. But you would have replaced most components on the PCB by this point.
Hope this helps.