Sony STR-V4 receiver, weird noise but only at startup

[ReVoxFan]

Hello AK Krew, I have a new patient on the bench that I've been poking at... Has anyone tangled with a Sony STR-V4 receiver that was doing similar to what this one is doing?

Upon startup, right after the speaker relays click to 'engaged', in both speakers I'm getting a sort of wind rushing into a microphone kind of sound. It isn't deafening, but definitely noticeable.

This occurs with the volume knob all the way down, or up, doesn't matter, so the problem isn't in the pre-amp section.

The wind rushing into a mic / rustling paper sound only lasts for perhaps 5 or 6 seconds; it fades out rather quickly and uniformly, and it does not re-occur again until the receiver is switched off, left to sit, and then restarted.

Has anyone come across this behavior before? It's a Sony, so think: Unnecessarily Overcomplicated

Cheers!

 

[avionic]

. It isn't deafening, but definitely noticeable.

One channel or two? Sounds like a noisy power supply.

 

[ReVoxFan]

One channel or two? Sounds like a noisy power supply.

I went back to the bench and hooked it up again to check, and of course today it has quieted down to nothing at all. I will ping it over the next few days to see if I can get it to misbehave. If memory serves, it was the right channel only but I want to verify that before spinning up too many grey cells. If both channels, then the PS is a clear suspect... but the quieting down of that wind rushing into a microphone sound, it only last for a few seconds before fading out pretty quickly. Definitely odd behavior. Cheers for the reply...

 

[knockbill]

yep,,, I noticed something similar to that in an old 1967? Fisher SS 220T,, replaced PS caps/diodes/resistors, and its been OK for 12 years..