Lil Peep, XXXTentacion Sued Over 'Falling Down' Track

Lil Peep and XXXTentacion straight-up jacked another artist's original guitar riff for their hugely successful collab, "Falling Down" ... so claims the artist in a new lawsuit.

Richard Jaden Hoff -- who used to go by the stage name K.R.i.O. -- is suing the late rappers claiming the guitar riff in his June 2018 Soundcloud track "Under My Breath" was sampled in Peep and XXX's track that dropped just 3 months later without his permission.

Specifically, Hoff claims his guitar riff in "Falling Down" is looped, sped up, filtered and equalized. He says that while Peep and XXX altered the riff, it remained substantially similar to the guitar part in "Under My Breath" and a blatant ripoff."

"Falling Down" quickly gained commercial success ... with over 20m plays on Spotify and over 21m views on YouTube. The single also hit No. 13 on Billboard's Hot 100.

The track ultimately landed on Lil Peep's second studio album, "Come Over When You're Sober, Pt. 2."

There's some weird timing here -- XXX was shot dead 5 days after Hoff dropped his track on Soundcloud. Lil Peep had already died following an overdose in November 2017 -- so, "Falling Down" was a posthumous hit for both rappers.

What's really odd is Hoff's lawsuit, for copyright infringement, is written like Peep and XXX are still alive. He's NOT suing their estates and refers to both of them in the current tense and says they're residents of California. Might be time for a Google search, Hoff.