NAD C326 troubleshooting

Is anybody who owns the NAD C326 familiar with the protection circuit issue. It shuts off even without playing music. On some forums was mentioned that if the PC is source of the music, that might cause the problem
since the PC gives everything from 1 Hz and above. My source of the music is the PC. Just yesterday the NAD went to stand by 4 times until completely died. Is that the fact or is the NAD just poorly designed amplifier?