While I can not second guess your technician, perhaps the problem may not be that severe. The Bose Companion 5 is only on standby when plug (having no power switch) and therefore the power supply circuitry is the only one working. Chances are it will be only the +5VDC logic supply that is really turned on at that instant. All others would be OFF hence my belief that the problem may be limited to the PSU and/or part of the logic board. Perhaps you can suggest to your tech to test the logic board (motherboard) using an external +5 supply. All others can be be tested and repaired using component replacement.
Should you not be comfortable going this route, perhaps you best bet would then be to get in touch with Bose or their local representative.
You can try looking over the country here
and the page will display a Bose contact information.
Say the Philippines would be:
Eleksis Marketing Corporation
Unit 206 Fox Square Building
53 Connecticut Street
San Juan City, Metro Manila, 1500, Philippines
Email: Click here to send them an email
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kind regards.
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