I have noticed a few posts that describe problems with low-frequency sounds, which are completely different from typical tinnitus noises.
If you hear low rumbling noise, like an engine, around the 40-100Hz frequency, check out thehum.info/ and see if this helps to diagnose your problem. Unfortunately, there is no suggestions about a cure unless you think you can identify an external source of the noise. White noise can give relief, especially if you hear the lower frequencies that also cause a feeling of pressure and vibration on your ears.