SiriusXM announced today that its SXM App, which delivers more than 425 SiriusXM channels of the best in audio entertainment – Howard Stern, ad-free music, sports and more – is now available to tens of millions of Comcast customers nationwide on Xfinity X1, Xfinity Flex and XClass TV, giving its subscribers a new way to experience SiriusXM programming at home. More than 425 SiriusXM Channels Now Available on Comcast’s Entertainment Platforms With the SXM App, customers can stream Howard Stern’s two exclusive channels, more than 330 channels of ad-free music from virtually every musical genre, …