Rabepobemababe
Member
I am happy to report that I received a replacement main-board from the vendor of SMSL SA-160 this afternoon. After replacing the main-board and testing the amplifier with different sets of speakers, I found the amplifier to be very silent. The high-frequency background whine is now gone. Just to be on safe side, I am running the amplifier with a 24V 6A adapter only, and not with the 36V 5.7A it was supplied with.