UPDATE: In a question and answer session Viacom said Harmonix made a loss of around "$65 million" for the financial quarter. "That loss reflects how we've been informed by the potential buyers we've been talking to," it said. The loss would have been half that number otherwise.
"Third parties have a different economic view of Harmonix. It will be worth more to them than it is to us," said the media giant. That's why it's selling.
Viacom plans to sell Rock Band and Dance Central developer Harmonix.
No explanation was given in its financial report, but Rock Band 3, released last month, appears to have failed to achieve commercial success.
"Viacom also announced that it plans to sell Harmonix, which developed the Rock Band music video game franchise," said Viacom. "Accordingly, the Company reclassified the business as a discontinued operation and has recast its results from previous periods to reflect this change."
In a question and answer session this morning, Viacom commented briefly on its plan to sell.
"We expect that [sale] to be completed expeditiously. We'll announce the results when the deal is concluded. The proceeds will go into our back account and then we'll deploy it," said the company
Official UK sales figures from UKIE revealed Rock Band 3 sold just 7386 units for the week ending 30th October in the UK.
As a result, Harmonix's tour de force spent a debut week at 26th in the UK all-formats top 40. Rival Guitar Hero: Warriors of Rock finished one place below in 27th.
All this despite the game being ruddy brilliant.
Earlier this year Harmonix boss Alex Rigopulos declared "I absolutely do not believe that rhythm-action gaming has reached its peak".
Viacom bought Harmonix, which used to develop Guitar Hero, four years ago for $175m. Rock Band's generated over $1 billion in revenue, but some critics suggest the music genre is dead.