How Much Force Should the Valsalva Manoeuvre Take?

I mostly use this as an indication of how closed my Eustachian tubes are at the moment. Sometimes it hardly takes any effort at all, and at other times it won't work at all, even at the highest pressure I am comfortable with applying. My right side also tends to be more closed for some reason, on average at least.

Sometimes when I do the manoeuvre air does get into my ears, but they don't do the regular popping thing, and still with a lot of difficulty, like something is obstructing my tubes.

I have had this for about 5 years I think, I can't really remember how it should be when everything is working properly, does someone know?

 

FYI: I believe someone on the board got tinnitus because of doing valsalva maneuver. I believe it was @Telis.