Hi J,
I've listened to the video and think that the two most likely possibilities are:
1. The (micro)SD card is corrupt and needs to be replaced or re-flashed or
2. There is a hardware fault and the B2 needs to be repaired.
There is a well documented procedure for re-flashing the (micro)SD card, but if your B2 is under warranty you might not want to do that.
Let us know what you think.
Regards,
Peter.