Something has - I think - destroyed the motor run capacitor on my heat pump, but I am not sure what it is.

Back story:

I have a Goodman 3.5 ton heat pump, model ARUF036-00A-1A. Two nights ago I woke up to the smell of something electric burning, and the sound of the blower motor stalled while trying to start.

The motor run capacitor is a 7.5uf and 370v, part number 27L566. I picked up a replacement capacitor, which is the same except it is rated 440v/370v at the recommendation of the local HVAC shop. This is a Mars #12931. I installed that, turned the HVAC power on, and it worked fine.

At that time I noticed a transformer (see below, left side) in the air handler was buzzing, and I don't recall it making any noise before. I looked at it, and the fuse that is installed was not blown, so I buttoned things up.

Last night I again woke up to the smell of something electric burning and a stalled blower motor. I turned the power off to the heat pump.

I took photos of the heat pump innards, CLICK to get full-sized image:

Transformer on the LEFT is buzzing:

Motor run capacitor:

Can someone tell me if this is a simple fix - is the transformer? Computer board? Or do I need to call someone?