Viacom , which had paid Harmonix $ 150 million following the success of Rock Band in 2007 , began seeking a `` substantial '' refund on that investment after weak sales in 2009 .
Viacom , which had previously paid Harmonix $ 150 million for their performance behind Rock Band in 2007 , are now seeking to get a `` substantial '' refund on that amount due to the weak sales in 2009 .