Currently Being ModeratedSep 19, 2011 5:01 PM (in response to yidoc)RE: Pantalla de Pod XT Live en blanco y parpadeando
One important tip to remember about any amplifier's speaker outs is that you should never connect them to the inputs designed for guitars, mics, or other instruments as you can seriously DAMAGE your hardware. ONLY connect speaker outputs to speaker cabinets or other devices specifically designed to handle the power from an amplifier's power amp.
From what you describe it sounds like connecting this way somehow sent the damaging current through your computer's USB ports and to the PODxt Live. You are lucky that you did not damage your computer and your POD HD500 as well.
If the PODxt Live is just power cycling you will need to take it to an authorized service center for repair: