I'm trying to diagnose an issue with my HK AVR520 - it randomly shuts down (self-protect mode, I think) after 15- 60 minutes of use. When re-powered on it runs for hours, no problem. It happens about 75% of the time I use the reciever.
I measured the resistance of the speakers to estimate the impedance and was surprised the value was only 3.7 ohms. I also checked my newer RS3-II's and they were also 3.7 ohms. Both manuals state 8 Ohm nominal impedance. Of course the HK manual states 8 ohm impendence is required. Any ideas other than taking the HK to the repair center (HK's recomendation)?