Hi Troutbc,
I am 5 weeks past my surgery, and am also experiencing symptoms in my good ear as you described. My neurosurgeon was able to preserve my hearing on the tumor side, and I'll have it tested next week when I go in for my first post-surgery follow-up consultation. I have pretty loud tinnitus almost all of the time in that ear, and it also becomes very muffled at times, but that comes and goes. I did have a brief 15 minute period about a week ago when it seemed that I was hearing perfectly fine out of the "bad" ear, so I have hope that my hearing may return to normal on that side some day. I feel very blessed and fortunate to have any hearing on that side at all.
With regard to your question and my good ear, I get occasional tinnitus on that side too, but it usually is only for a brief period of time - sometimes less than a minute. The hearing in that ear will often sound like it's muffled too, and that sensation can persist for long periods of time. However, I think it may be a "phantom" sensation because I can snap my fingers next to my ear when it feels that way, and can hear that just fine.
I also experience popping in both of my ears sometimes, like the pressure is trying to adjust. I also occasionally get a clicking sound, similar to the popping, but seemingly centered and "heard" inside my head rather than being heard within my ears.
The other hearing issue I had, which came on about a week after my surgery and lasted for a week or so, was that I heard people at a higher pitch than normal - almost like they had inhaled a bit of helium. Their voices weren't super high pitched, but just higher than normal enough that it was definitely noticeable. Some voices also took on a "mechanical" or "robotic" sound - like I was hearing multiple pitches at once. Both of these effects occurred in both ears, and were very strange. As noted, these effects stopped happening after about a week.