Howard Stern went to Sirus for 1 reason. Opie & Anthony. XM offered him a similar deal but he would have had to share top billing on the XM High Voltage channel with them and he hates those guys.
Stern actually was afraid of the competition from them when they all were on Infinity. He had Karmazen put gag orders on them from mentioning anything about Howard Stern on the air or to the press.
He was also instrumental in having Infinity keep paying and keep O&A off the air for the last 2 years of their 3 year, $30 million contract after the Sex in St. Patricks fiasco. They were actually paid $20 million to sit on their asses for 2 years because of Stern. Stern was motivated to have Karmazen do this because he didn´t want O&A to go head to head with him in the mornings for another company.
It was after I learned all this that I lost all respect for Stern and saw him for the hypocrate he had become.