Beats Music’s first 100 days on the market have been a huge disappointment, with label sources estimating the service’s paid subscriber count is in the “low six figures.” That conflicts with reports from company insiders claiming the service is being used by “millions of people,” and has actually exceeded internal projections. The service recently updated its iOS app to allow for in-app purchases, seemingly in an effort to drive higher adoption numbers.

 Two of music’s most successful brand marketers, Jimmy Iovine and Dr. Dre, are in the hot seat as label sources grouse that the first 100 days of the duo’s subscription streaming service, Beats Music, has been a disappointment and soon will face competition on the mobile platform when Sprint begins bundling Spotify with its “Framily” plans. Spotify founder Daniel Ek will debut the rival wireless partnership — a direct challenge to Beats Music’s alliance with AT&T — on April 29, at a time when a number of label sources are expressing concerns that Beats, which launched in January, has yet to catch fire in the streaming music market. “Jimmy is finding out this is tougher than it looks,” says one senior executive. “This business takes time.”