1. out of tune
That guitar sounds completely out of tune.
The concert didn't go well. They were playing out of tune.
Your violin sounds awfull!!! I think it's out of tune.
sing out of tune
I’d join a choir if I didn’t always sing out of tune!
Anglais mot "fałszujący"(out of tune) se produit dans des ensembles:
New Matura Success Upper Intermediate, Unit 4