We advise using a Roland PSA-120S or PSA-120T power supply only. These PSA power supplies are voltage regulated and 3rd party power supplies can cause the unit to not operate properly.
A new PSA power supply can be purchased through a local dealer or online:
https://www.roland.com/us/dealer_locator/
https://www.google.com/search?q=BOSS+PSA-120S&ie=utf-8&oe=utf-8