Suggest Treatment For Blocked Ear

Question : For about 3-4 weeks, I have had a little bit of blocked/muffled sound in my right ear. I went to my doctor, and they removes some wax up against my ear drum. The problem got better. It returned about a week later, and now I have the same feeling in both ears. I went to my ENT, who did a "thorough" exam on my ears, including a hearing test . She found nothing wrong, and the hearing test was normal. Since that visit, my ears have gotten worse, as far as feeling plugged and especially muffled. I now get slight high-pitched whining in both ears of varying degrees. Occasionally when I swallow, it feels like my left ear may pop open somewhat, but she tells me my eustachian tubes are clear. She has no answer as to what the problem may be, and told me to come back in 3 months for a follow up. I am a 60 year old male in othewise good health. Im getting more than a little concerned. Can you shed any light at all on the possible problem ?

She also mentioned possibly getting an MRI to check for a brain tumor...which is the crux of my worry. She also said my eustachian tubes are not blocked after testing....could she be wrong ?