Our TS501 decided it didn't want to turn on anymore. My tech thought it was just a dead battery, but when he plugged it in, it started to emit a constant high pitched beep and displayed the message "Software Unauthoried" I saw there was a software update, so I put the SD Card into my computer, loaded Maxi PC Suite V1.28 and updated the SD Card. Put the card back in the unit, and it still displayed the message with the beep tone. Looked on the forums and online for solutions. I uninstalled and reinstalled the software on the SD Card, no change. I reformatted the SD Card, reinstalled the software, no change. I hooked the unit directly to the computer, Maxi PC Suite didn't recognize the unit was even plugged into the computer. I tried holding the power and "Y" buttons for a hard reset, no change. The moment the unit is plugged in to a power source (AC Adapter, or USB) it lets out that constant beep tone until it is unplugged. If I try to start the unit without the SD Card installed, it shows on the screen to put the card into the unit but still lets out that beep tone. the screen displayed that the unit is version 2.61