An AI music detector built into the Treblo app flagged the viral summer hit "Rubberz" by Fenix Flexin as "very likely" AI-generated, following weeks of fan debate about whether the song's polished voice matched the rapper's earlier work.
The detector also flagged a Tyga track as likely Treblo-made.
Music producer Medasin had posted videos claiming he identified Treblo as the app behind both songs, pointing to evidence in Fenix's Instagram posts and showing he could recreate similar tracks using the app's "80s synthwave" and rap-lyric prompts.
What happened
Treblo, a generative AI music app, released a detector tool over the weekend that flagged Fenix Flexin's "Rubberz" (currently No. 58 on the Billboard Hot 100) as "Very likely Treblo"-made, and flagged a Tyga track from early July as "Likely Treblo." Music producer Medasin had posted videos claiming both artists used Treblo to create their songs, pointing to evidence including a filename suffix visible in Fenix's old Instagram Stories.
Why it matters
"Rubberz" has been debated all summer—the song's bright, polished voice doesn't match Fenix's recognizable nasally tone from his earlier work with Shoreline Mafia, and both Fenix and producer Purps on the Beat denied using AI despite suspicion. Treblo's detector claims a false positive rate under one in 10,000, potentially settling a dispute fans could not resolve before. The detection comes as platforms across the web (LinkedIn, Substack, Tidal, Spotify) are beginning to label or block AI-generated content.
What to watch
Treblo's detector is open-source, so anyone can inspect and test the code. Requests for comment to Tyga's label and to Fenix and Purps went unanswered. The tool uses tags like "80s synthwave" and rap lyrics to generate songs with consistent lyrical structures (recurring "finger/linger" rhymes, references to rings, glass, and pockets). Medasin demonstrated he could generate similar-sounding tracks by entering identical prompts.
Fenix Flexin's "Rubberz," officially released in June, climbed to No. 58 on the Billboard Hot 100 and accumulated 7 million views on its music video, marketing itself as a rap track with boasts about cash and jewelry and bars working as double entendres for braggadocio and depression. Yet the song contains a central oddity: it is not a rap production at all, but a synth-pop tune that would fit comfortably in a moody 1980s playlist. More strikingly, the vocal delivery sounded nothing like Fenix's established voice. Fenix Flexin, who grew up in East Hollywood and gained recognition as part of Shoreline Mafia in the late 2010s, carries a distinctive somewhat nasally, congested voice that made his bars easily identifiable. The voice on "Rubberz," by contrast, is "a lot brighter and crisper," with an accent closer to a very chipper Morrissey than to Fenix's original tone. Both Fenix and credited producer Purps on the Beat denied AI use at every turn. Fenix told Channel 5 that he "freestyled" the lyrics, and in comments on an On the Radar performance, he replied to AI accusations: "No sirrrrrrr, recorded same as all music I do! Only difference is auto-tune reverb and me using my fake uk accent lol." Despite these denials, well-known AI music detectors did not flag the track, leaving fans in a summer-long debate with no definitive resolution.
On Thursday, music producer Medasin posted a video claiming he had identified how Fenix created the track. The culprit, he argued, was not Suno or Udio—the two most prominent generative AI music tools—but a lesser-known app called Treblo. Medasin's evidence was systematic: he noted that Treblo's app used to be called Sonauto until two days before "Rubberz" dropped, then presented a screenshot from one of Fenix's old Instagram Stories in which a filename visible on screen carried the suffix "Sonauto.mp3." Most compellingly, Medasin showed that using Treblo himself, with tags like "80s synthwave" and a prompt requesting lyrics about "rapper lifestyle," he could generate a strikingly similar track. His generated song produced "Diamond chains hanging heavy" while "Rubberz" contains "Now I bought a heavy diamond chain." Medasin's creation yielded "I see your face in the champagne bubbles"; Fenix's song has "Still seeing your face in the glass." Both songs featured variations on "pockets thick" and mentions of "plastic smiles." "There's just way too many coincidences," Medasin told WIRED. "It is just a mathematical impossibility that he did not use Treblo." When WIRED tested Treblo itself using the same prompts, it confirmed that the app generated similar lyrical structures and sound—even with variations, combining an "80s" tag with a "rap lyrics" request produced comparable results each time. Treblo's engine, it appeared, favored certain recurring elements: "finger/linger" rhyme pairs, references to rings and glass and pockets, and song structures built around thematic transitions from night to day.
Fenix responded hours after Medasin's video dropped by posting to Instagram what he claimed was the original project file for "Rubberz," hoping to prove the song was created from scratch in a studio and not via AI. However, music producers immediately flooded the comments, many asserting that the project file looked suspiciously like someone had taken an existing song and used a stem separator—a tool that extracts a full song into rudimentary components like bass and drums—pointing back to AI generation. Hours later, Fenix deleted the post, and neither he nor Purps on the Beat have addressed the video or its deletion since; requests for comment sent by WIRED to both went unanswered. Two days after Medasin's first video, on Saturday, he released a second one alleging that Tyga's new $TARFACE project also uses Treblo, citing social media videos of the two artists together, their shared label affiliation, and a sudden shared pivot from rap to 1980s-themed production. More decisively, Medasin ran a Tyga song through a new AI music detector a friend was developing, and it flagged the track as AI.
On late Sunday night, Treblo released a new page titled "Was This Made With Treblo?"—a built-in detector tuned to identify songs made with Treblo "with little to no modification." The company stated that listeners should know what they are hearing. When "Rubberz" was fed into the tool, it returned "Very likely Treblo." Running a Tyga track dropped in early July returned "Likely Treblo." Treblo's site claims the false positive rate is under one in 10,000, though the detector's efficacy has not been independently reviewed; the code has been released under an open-source license so anyone can inspect and test it. Treblo cofounder Ryan Tremblay said in a statement that "someone appears to have used our model to find a sound that millions of people connected with," and that the company wasn't "even aware ['Rubberz'] existed until after it hit the Hot 100." Requests for comment to Tyga's label went unanswered. The detection moment arrives amid a wave of platform gestures toward AI-content labeling: the same day Medasin posted his first video, LinkedIn rolled out a "seems like AI" button for flagging AI content; Substack had released an AI-newsletter detector two weeks prior; Tidal has blocked monetization of AI-generated music; and though Spotify lacks an official AI tag, a crowdsourced tracker allows listeners to report suspected AI content. Yet reaction in the comment sections of Medasin's videos revealed a third camp: fans who said they liked "Rubberz" regardless of its origins, who framed AI as the future, or who accused Medasin of jealousy. Medasin acknowledged the song is catchy and admits it stayed in his head "for a fucking month." Ultimately, he argued, there can be a place for AI in music—but only if artists disclose it honestly. "This is, like, a critical moment in music history," he told WIRED. "I have very, very deep respect and love for the journey of musicians and humans and human experience being celebrated and present in music." He condemned deception: "It is unethical to me on a very spiritual level."
The dispute over "Rubberz" reflects a broader moment in which platforms and creators are struggling to label and define AI-generated content. Fenix Flexin's vocal performance represents a dramatic departure from his recognizable style—his history with Shoreline Mafia in the late 2010s established a distinct nasally voice that made his bars identifiable. The sudden arrival of a bright, crisp, Morrissey-inflected vocal on a synth-pop production in June raised immediate suspicion, yet no widely-used AI music detector flagged it at the time, leaving fans in a state of unresolved debate throughout the summer. Medasin's methodical breakdown—combining the Sonauto filename evidence, visual recreation of similar lyrics using Treblo's interface, and thematic overlap in word choice ("finger/linger" pairs, references to rings and glass)—brought the accusation into sharp focus and prompted Fenix to post what he claimed was proof of a studio project file. The subsequent deletion of that post, combined with music producers' observations that it resembled a stem-separated reconstruction rather than an original session, appeared to confirm rather than dispute the AI accusation. Treblo's decision to release its detector tool and flag both "Rubberz" and Tyga's track lends institutional weight to the theory, though the company notes its detector's efficacy has not been independently reviewed. The timing aligns with a broader wave of AI-content labeling initiatives across platforms—LinkedIn, Substack, Tidal, and others have rolled out detection or flagging features—suggesting the music industry is catching up to years of image and video generator concerns.
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