What Causes A Strange Smell And Taste Always?

I seem to have developed a "strange smell and taste" throughout the last year and it seems to be getting worse.

I always have a "post nasal drip" and some phlem, but i don't know if that has anything to do with this smell and taste. It's not a bad taste or smell, almost like Marmite or yeast, difficult to really pinpoint it.

Other day I had very painfull ear and after about 2 weeks now it still seems to keep lingering in the background (earache). I always have a pure white tongue, Candida or something, can not get rid of it for years already.

I am a male, 50 years old, 1.9 meters long, 65 KG weight and I sometimes get some mouthsores as well.

I don't really have a bad "medical history" but my immune system was always a bit low.