"Humming Sound" on Track Power Up (TMCC can motors).

Chipset,

I have a similar issue on one of my Lionmaster SD90s Although I believe the hum is from the speaker. When I asked the same question the consensus was it was an audio board issue. Can you confirm if the hum is coming from the motor itself?

Jay in Ottawa

Before you're moving, the motors should make no sounds.  Jay is right, most likely the audio.

Odd, because the audio sounds really good.

When I say hum, I am talking about, I turn on my power strip, track lights up.

Increase transformer to 18volts, and then I hear a hum on some TMCC locos, not all.

Start up loco, audio sounds good, no more hum.

using C&C on a Legacy 990

The hum is a background hum.  I hear it with many older locomotives.  Of course, it could be something else, your hum would be my hum.   It's pretty difficult to quantify in ASCII if it's normal or abnormal.

In the video, there are two SD40-2T's; the one that you are watching with it's speaker turned off, and is already started, BUT.....the other is "not in view", and has NOT been started...and you can hear the sound it is making in the background, just sitting there and not started.

Ignore the sound of the smoke unit, that has been fixed.

I cant hear anything, even at max volume. 

I can - it's quite clear and all too familiar to me. 

In case someone has an insight on this, I have the same problem but quite a bit worse with TWO Vision line engines. The buzz on applying power to the track is very distinct although it decreases slightly if I push the voltage up a notch from 18V. Haven't tried opening up the body shell/tender but if this is an audio board issue I doubt that just re-seating them will cure it. Does anyone know what the exact cause might be? I have wondered about some kind of track/signal interference but the problem only arises with those couple of locos.

That sounds like a bad capacitor on the P/S board.