Sounds like you have an older 4 cylinder car. I had a Pontiac 2000 4 cylinder that did that.
I have heard that if you have papers or napkins in the glove compartment box they can get sucked into the air vent which then makes a humming noise that you can hear while driving and as you increase the speed the pitch of the noise gets louder.
One possibility could be a bad wheel bearing.
2001 buick lesabr // when recirculate speed doesnt change only make humming sound rest of heater works fine
it could be the fuel pump
If the noise gets louder with speed, it is possible that the bearing in one or more of your wheel hub assemblies have failed. The noise will also become more pronounced during steady state corning.
Most likely a bad tire.
The speed of sound depends on what the sound is going through, not on what created the sound. If sounds from different sources had different speeds, then there could never be a band, orchestra, or choir.
Check the fluid level in the transmission. Sound like a part may be going out inside the torque converter or transmission itself.
Sounds like you are having transmission troubles, or your gears are not shifting correctly. It's like it's stuck in nuetral. You should never put your RPM's above 4 or 5, you are going to blow your engine out.
Because the color wheel is going bad (it what makes the TV sound like a small airplane taking off). Even if you found a replacement part, I'm told that the color wheel is impossible to properly calibrate, outside of the factory, so your best bet is to turn up the sound.
Check your fuel pump
Bad wheel bearing.