80s-90s film with cassette and chip implant that gives special abilities

Hi. I saw this film maybe 20 years ago and could not find it ever since. It started to haunt me, I tried various websites, but no luck.

It’s 80s-90s film. Most likely american. I remember only parts of the film. Somebody there found a cassette (yes, the old school audio cassette). A there was some phone number there and mabye some chip inside (not sure about that). The character who found the cassette called the number a was taken into a kind of a facility. There the character was implanted with the chip, somewhere in the head. The chip gives the person special abilities. I remember 4 people meeting after the chip implant and suddenly they could speak like 25 languages, knew a lot about biology, chemistry, etc. And also they knew martial arts.

Thats pretty much all i remember, only vaguely I recollect there was some homeless guy who found the cassette again at the end of the film.

Thanks a lot for any help.