Hi i have a low rumbling sound in my left ear which goes when i move my had but returns when i relax again. ?

I would think: this is most likely something we call an "audible bruit." A bruit is the rumbling or pulsing sound or sensation made by blood flowing through a vessel. When you move your head, the position of a blood vessel near your ear may change, perhaps narrow a bit, and allow you to hear the sound. It is not uncommon, is usually benign. But see your doctor to determine if further testing is warranted.