Well, I think you need to contact Sony. Here is a link to a site that list contact information. It will provide information on e-mail, live chat or web based support options. I would suggest e-mail or live Chat and I would be very up front with them concerning the cause and symptom of the issue. There may be a reset feature available to reset the protection circuit. If not, Sony usually provides a fixed price for repairs. When I enquired about a different ES receiver a couple of years ago, the repair cost was $125.
http://esupport.sony.com/perl/support-contacts.pl?template=EN
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