Hello all, recently I've notice a faint whining noise coming from what I believe to be the transmission. It's only in drive or reverse, not neutral or park. It is present when idling in drive and changes with the rpm. I think it’s been making noise for a while, but I didn't notice because the fuel pump was failing and before that, the muffler needed replacement.

Is this anything to worry about? I've heard some noise is normal, but this is present in second gear as well before it’s drowned out by engine and road noise. Transmission fluid has been changed at least 3 times recently, its a decent red color and at the perfect level