I am not sure how describe the problem I am having. I own a Honda Accord 5Speed manual. I have 56,000 miles.

When I drive down the highway, my accord starts humming on acceleration. When I get to 65, I can hear the sound clearly. It does not sound like the motor though. I did a hold down the accelerator driving and hold down the brake at the same time that is when the humming stopped.

The sound sounds like it is coming from underneath the hood. Any help or idea what it could be would be appreciated. Thanks.