I Have Been Experiencing Irregular (not With Heartbeat) Pounding And

I have been experiencing irregular (not with heartbeat) pounding and fullness in my ears. The spells always last about 7 days and repeat about every 6-7 weeks. When these spells hit, I tend to feel very sleepy all day while it is happening. I noticed that the one thing that sometimes makes it stop is if I am sitting crossed legged on the floor (meditating). All I have to do is sit down and the pounding stops. I have not found anything online that is very similar to my experience. Any help or direction will be greatly appreciated.