The followings are possible causes for YouTube videos not being displayed on the SESSION screen of BTS for KATANA-AIR (Ver. 2.0.0 or later).
No Internet connection
Connect your mobile device to the Internet and then restart BTS for KATANA-AIR.
You may be selecting a video for which embedding is not allowed
Videos for which the content owner has prohibited embedding cannot be played back.
NOTE: With the combination of KATANA-AIR System Program Ver. 1.30 or earlier and BTS for KATANA-AIR Ver. 2.0.0, some restrictions exist on connections and functions. To use the functions added to BTS for KATANA-AIR Ver. 2.0.0 with KATANA-AIR, please update the system program to Ver. 2.00 or later.
For details on the limited functions, see "BOSS TONE STUDIO LIMITATIONS WITH KATANA-AIR VERSION 1.30".