Thanks for rechecking the sound levels.
I had a very similar experience regarding singing. Our class was practising and the teacher kept saying "somebody is singing flat." She kept walking amongst us trying to find the "culprit." Then the boy in front of me very helpfully turned around, pointed his finger at me and said "It's him, Miss." As you can imagine this made me feel great. The problem duly identified I was instructed to just mime in the coming public performance. Very recently (ie nearly 50 years later) I told my partner I never sang, even though I would have loved to, because I sing flat. She got me to do a do re me fa's (she has a lovely singing voice) and declared "There's nothing wrong with your singing."
Next up, instruments. At school, bored with the recorder, I said I wanted to play a clarinet. Sorry, all allocated, but we do have a bassoon. Cue six months of fighting with a bassoon. I got to a mediocre standard on a drum kit, but I should have had lessons. I also suspect our neighbours wouldn't have been impressed. My final attempt was alto sax (must have been in my jazz period). I was OK and had lessons but after about a year I gave up, I think it just fell out of my daily life, probably lost out to socialising (ie drinking beer
)
I believe you
are qualified to comment, your ears are connected to your brain (I hope). Plus you have many years of listening to draw upon. My music creation only comes from an app (a very good one) so I'm not exactly hi-tech!
Thanks again for your help.