low pitch rumble affected by head position?

Hi all --

I've been lurking here for a week or so and am grateful for this community.

After a bout of unilateral Sudden Hearing Loss this Spring, my neurotologist now thinks I may have cochlear hydrops.

The initial hearing loss was most profound in higher frequencies, but there was some loss in lower frequencies, too. A course of oral prednisone brought the lower frequencies back to normal and improved things a bit in the higher frequencies. Did three inner ear steroid injections after that, which brought a little bit of additional improvement but then hearing started getting worse again in the lower frequencies. It was at that point that my neurotologist said it might be cochlear hydrops, or (less likely) autoimmune ear disease. He suggested we give it a month, see where my hearing is at and come up with a treatment plan from there.

I'm about three weeks into that month, and have noticed some additional fluctuation. More recently, in addition to the high-pitched tinnitus I've had all along, I've started hearing a low rumbling sound that is affected by the position of my head. It's loud when I look down, and can be silent when I look up (especially later in the day). From what I've read online, I might be describing a "venous hum," but it's never pulsatile (always a steady low pitched rumble), and it doesn't seem to be affected by manipulating my jugular.

I'm curious if others have experienced a similar rumble that changes depending on head position?

For what it's worth, I've been trying anti-virals over this month, specifically 1g Valacyclovir 3x/day. (My ENT wouldn't prescribe, but my GP agreed to.) Day 13, and no results yet. Hoping against hope that it'll kick in and that I'll see some improvement. I've also been keeping my sodium intake below 1500mg.

Thanks for any thoughts you might have.