Ask around in Raon.

I used to know someone there from way back that does all kinds of audio repair.... from consumer HiFi to professional gear. He's the go-to guy for even the so called {insert brand here} authorized service center when they're stuck on a particular problem or fault. Sorry but this was over 2 decades ago and I've lost track of him. Though, I'm sure there's at least a few "master" technicians still working in the vicinity.

Anyway, look for a technician that owns or leases his own space. Wag yung nasa bangketa lang.