If your alarm played the backup alarm sound instead of the music you selected, check the following:
The music service or internet radio app you selected may not have activated.
Your phone may be out of range of your ROLL – make sure the two devices are within 65 feet of each other.
The Bluetooth connection is off on your phone or your phone is in Airplane mode – make sure you keep the Bluetooth connection on.
Your phone may be off or out of battery – make sure your phone is on (your alarm will still play if your phone is Locked)
Your phone may have lost the connection to the internet/network.