I'd guess it belongs to some kind of controller. I don't know what it controls, but there's a LOT of DAC action going on on that board, and I'm going to have to assume it's translating digital input into analog signals to control something like machinery or lighting, what-have-you. Doesn't appear audio-based, though.

Festo = pneumatic contol equipment. With the parallel ADC I'm guessing it's for a position sensor or something.

I guessed it was something like that 😀
Are the caps worth salvaging? Or should I pass this on.

Also, that little EPROM, could it be an BASIC on chip?
It has marking that follow:
ML 1800 CPU
80 SYS 2.0 --
(C) O. E. M.

Its has CPU written on it... I'd guess this is a processor rather than an (E)EPROM. The only sure way to know would be peeling the sticker, but if this is actually an EPROM than this wouldn't be advisable.

I can feel an circular engravement in the middle (EPROM glass dome).

You could try reading one of those with an (E)EPROM reader and look for strings there to give you more clues... but googling for ML-1800 gives me random equipment, some of those being industrial-grade stuff. My educated guess is that this is a ROM for an industrial machine, which isn't far fetched considering that the parcel also had FESTO control stuff on it.