As reported by the insurmountable TMZ, it seems Shawn Fonteno, the voice actor behind the "Franklin" character in Grand Theft Auto V, allegedly knocked Ice Cube out and stole his chain way back when.
Fonteno is a former rapper who operated under the moniker Solo. He describes the altercation in the documentary "Beef 2", claiming he dropped and robbed his fellow emcee over a "business dispute" in the '90s, which was apparently part of the feud between Cube and Cypress Hill at that time. Fonteno was on Cypress' side. As for details, he says "the streets will tell you."
There doesn't seem to be any bad blood, though - not on his end, at least. Fonteno even told TMZ he'd like to work with Ice Cube in the future. "We both hustlers homie, it is what is, you know? He’s from South Central, I’m from South Central, that shit's over with man... Holla at ya boy!"
Peep his testimonial and the "Beef 2" footage below: