My Voicelive Rack suddenly froze during use and now it won’t boot anymore. When power up the unit it just remains in blank blue screen. uMod button has led indicator on, all other button leds are off and the unit does not respond to any buttons. I have found from support forum similar issues and recovery SW boot images for other Voicelive family products, but nothing for Voicelive Rack. Could you post instructions on how to try to recover from this issue?