Fenix Flexin’s “Rubberz” has become one of the more unusual music debates of the summer: a popular track with a throwback synth-pop sound, a rap artist at the center, and a growing argument over whether generative AI helped make it.
The discussion has now moved beyond fan suspicion and producer analysis. Treblo, the lesser-known AI music app at the center of the claims, has published a detector that is flagging songs made by both Fenix and Tyga as likely AI generated.
Why “Rubberz” drew attention
“Rubberz” was officially released in June and currently sits at #58 in the Billboard Hot 100. Its music video has 7 million views, and the song has been treated by many rap listeners as a serious contender for the season’s defining track.
But the song also arrived with a twist. The track is not built like a conventional rap record. It leans into an ‘80s-style synth-pop sound, with a vocal performance that listeners found strikingly different from what they expected from Fenix Flexin.
That difference mattered because Fenix was already known for a recognizable voice. The source article describes his earlier sound, including his time in Shoreline Mafia in the late 2010s, as noticeably tied to his East Hollywood background and his somewhat nasal delivery. On the June 5 release of “Rubberz,” the voice was described as brighter, crisper and much harder to connect to his previous recordings.
Fenix Flexin and credited producer Purps on the Beat have denied using AI. Fenix told Channel 5 that he “freestyled” the lyrics. In comments on an On the Radar performance, he responded to accusations by writing: “No sirrrrrrr, recorded same as all music I do! Only difference is auto-tune reverb and me using my fake uk accent lol.”
The Treblo theory
The debate sharpened after independent music producer Medasin posted a video on Thursday claiming he had identified how Fenix could have made the track with AI. His claim did not center on Suno or Udio, which the source identifies as the two most prominent generative AI tools for music. Instead, Medasin pointed to Treblo.
According to Medasin, Treblo had previously been called Sonauto until two days before “Rubberz” was released. He also highlighted an old Instagram Stories clip from Fenix teasing his new ‘80s sound. In a freeze-frame, a visible filename appeared to include the suffix “Sonauto.mp3.”
Medasin also attempted to reproduce the effect. By using tags such as “80s synthwave” and prompting the app to write lyrics about a “rapper lifestyle,” he generated a track that sounded similar and contained overlapping lyrical ideas.
The comparisons in the source include several examples:
- Medasin’s generated lyric “Diamond chains hanging heavy” was compared with “Now I bought a heavy diamond chain.”
- Another generated line, “I see your face in the champagne bubbles,” was compared with “Still seeing your face in the glass.”
- Both songs were said to include some version of “pockets thick” and both mention “plastic smiles.”
Medasin told WIRED: “There's just way too many coincidences,” adding, “It is just a mathematical impossibility that he did not use Treblo.”
Why the project-file response did not end it
Fenix later posted a video on Instagram showing what he said was the original project file for “Rubberz.” If authentic, that kind of material could support the argument that the song had been made in a studio rather than generated as a complete AI track.
But the post did not settle the matter. Music producers in the comments argued that the file looked like an existing song had been separated into basic parts, such as bass and drums, using a “stem separator.” That interpretation would leave open the possibility that a full song had first been created elsewhere, then broken into components.
Hours later, Fenix deleted the post. The source says neither Fenix nor Purps On The Beat has addressed that evidence video since, or explained why it was removed. WIRED’s requests for comment to both went unanswered.
Tyga and the wider AI music question
The argument expanded two days later on Saturday, when Medasin posted another video alleging that Tyga’s new $TARFACE project also appears to be at least partially using Treblo.
Some of the connections Medasin raised were circumstantial. The source cites social videos of Tyga and Fenix together, their shared label connection, and a similar shift from rapper to ‘80s-style crooner. Medasin also said he ran a Tyga song through a new AI music detector that a friend is developing, and that it was flagged as AI.
Treblo’s own response made the story more significant. Ryan Tremblay, Treblo’s cofounder, told WIRED: “Someone appears to have used our model to find a sound that millions of people connected with,” and added, “and that's exciting.”
Tremblay said Treblo had not previously spoken to Tyga or Fenix. He also said the company was not “even aware [“Rubberz”] existed until after it hit the Hot 100.”
The detector changes the debate
Late Sunday night, Treblo published a page titled “Was This Made With Treblo?” The page functions as a Treblo music detector. A blog post describes it as a tool “tuned to detect songs made with Treblo with little to no modification.”
That matters because the argument over “Rubberz” had previously been stuck between denial, fan suspicion and third-party analysis. Well-known AI music detectors had not flagged the song, according to the source, and Fenix continued to deny using AI while the track gained attention.
Now the app connected to the allegations has added its own detection layer. That does not answer every question about authorship, studio work, editing, vocals or creative control. But it does shift the conversation from whether listeners can hear AI in a song to whether a platform can identify music made with its own model.
For artists, producers and listeners, the “Rubberz” debate shows how quickly AI music questions can become part of a song’s public identity. A hit can now be judged not only by how it sounds, but by whether its sound can be traced back to a generative tool.