When Google introduced Chromecast, one of the biggest selling points was that it was device-independent. It didn’t matter what version of Android you were on, as long as you had the Chromecast and updated your apps to support it, you were good to go. For the most part, that holds true, just not for Verizon Droid RAZR owners.
Apparently, there is some kind of bug with the RAZR that prevents it from casting anything from Google Play Music or Google Play Movies & TV. The icon for casting simply doesn’t appear. The bug doesn’t affect YouTube and Netflix apps, and other Verizon and Motorola devices are seemingly unaffected, so this is specific to just the RAZR, and likely the RAZR MAXX. It’s tough to tell if this bug is because of Motorola software on the device or simply a quirk in the updated versions of Google’s Play apps. I guess we’ll find out soon.
source: Droid Life