Pulsating Low Pitch Hum/Drone

Please help with mystery pulsating low pitch drone/hum2018 S. Jimny, purchased used in '22, low kilometers, WITH the noise (unfortunately noticed post-purchase). Non-modified, has factory recommend road tires. The sound is especially noticable on smooth roads between 40-70 km/hr but at any speed. It is not very loud and most people assume it is tire noise but it is not an even sound like you would get from tire tread, it is more of a pulsating sound. Going around turns or braking does not seem to make a diifference with the noise, applying clutch and gearing up or down or coasting out of gear (when it's best heard) makes no change in the sound. Important to note that the pulsation increases/decreases with velocity, suggesting rotational... I have installed a new set of tires since the noise started and it made no difference, and rotating tires did not help. The sound seems to come from the drivers side front (when windows up) but reading of this, the noise could be referring from the rear. When windows down, can't be determined (center?) It sounds like it could be a bad wheel bearing but after two years and a LOT of kilometers I would expect a wheel bearing to get louder and that has not happened. The sound has remained the same. I've had mechanics check and all systems  appear sound (brakes, bearings, gear related, etc.)I appreciate any help/suggestions. The noise drives me out of my mind, mostly due to that I don't  know what it is and if it would pose a danger while underway and cause us to drive off of a cliff if whatever it is gives out or leaves us stranded in remote areas (of which we travel through often).

 Important to note (and possibly related but probably a separate issue):when at speeds of 60-70km/hr and brakes are lightly applied, only when down hill (doesn't happen on flat smooth road) there's a slight vibration. Could this be the beginning of the infamous Jimny death wobble?  

This sounds like normal transfer box noise to be honest.  If the tyres are at the correct pressure (23/26 PSI) and the bearings are ok all round then it could be standard noise from the transfer chain.

The Jimny has a reputation for warping disks, sounds like you might have a slightly warped disk

Thank you Martin, this makes me feel a bit better.
The slightly warped disk:
Could you tell me which disk? I'm not a mechanic and would like to ask the mechanic I've been using to check the things suggested to consider here.
We are very rural in location and mechanics are few, and their resources even fewer.
Your help is much appreciated

Could try to change the tire pressure to see if the noise changes to rule out the tires. for a short period there is no harm in trying with a low pressure like 1.5 bar or a higher up to nearer to what the marking on the tire says is max

Do a Google search for "chassis ear" - essentially a set of microphones that can be attached to various parts of the car and you can switch from one to the next to narrow down the origin of the noise.

The original "Steelman" product is quite expensive, but there are reasonably priced chinese models that will do the job.

Change oil in transfer box
And replace the rear engine mount found at the back of the gearbox