2006 Subaru Outback loud humming

I thought it was the tired due to the cold weather. But now it is warmer the noise is still there. Bareknuckes previously mentioned wheel bearings as a potential problem. The car is driving (sound-wise) like I have some huge mud-bogger tires on or like crossing a cattle-guard continuously. so loud (in the cabin) that sometime I forget to shift (lol) because I hear the humming rather than the engine. What you guys think?

Have you always bought tires in sets of four and rotated them regularly, so that the tires always had the same circumference?

Old, worn, hard tires did that on my dad’s Subaru wagon some years back. The tire dealer diagnosed it and sure enough, new tires made all the diff.

If the sound changes when you take a curve or twitch the steering wheel, a bad wheel bearing is the likely source.