Tone Deafness is a matter of degree. On a scale of 0 to 10, I'm usually about a 3. Practicing & playing along to recordings can bring me up to a 6. A few beers can bring me down to a 1. Singing is hopeless, especially singing along with others. Playing with others can be okay, but I usually watch their hands as well as listen.

When I was a little kid the teacher told me to mouth the words silently when the class sang, I was so off-pitch.

However, being no good at something hasn't stopped me.