got covid 1.5 months ago. caused unusual flem while breathing. I had other symptoms but the flem was the most annoying...like cellophane on my breathing tubes rattling...so frustrating. it went away but ever since when I go from chest to mix or head - especially in AH vowel - the flem hits just enough to cause me to have to intermittently stop and clear my throat. I hope it goes away but for now as Ken says....keep sining through it!.