A little late to the party and my ears aren't so good but will try to help.
Assume you're actively driving in the audio clip we hear and the sound you're referring to is the oscillating humming noise?
If it's only while you're moving from what I can hear I'd recommend checking or having your mechanic check your driveshaft, the U-joints, differentials (doubt it but good to check) wheel bearings - btw to my ears it sounds just like a wheel bearing, if the noise only comes from one wheel then that's the culprit.
If it's when you're stationary, in park without the trans running I couldn't tell you what it'd be without a video or hands on.
If it's when you're stationary but in neutral, there you are, potentially the pilot or guide bearing that surrounds the shaft that inserts into your engine from the trans or something else in the trans as it should be the only thing moving aside from the engine.
If you have any questions or concerns feel free to DM me, hope you've gotten it resolved by now