Carlos Valdes has a ton of singing in his background on stage.
I've seen clips of John Wesley Shipp, Tom Cavanagh, Keiynan Lonsdale, and Tom Felton singing, and they all sound good.
Danielle Panabaker sang a little bit in a movie once, so she can do it. Just don't get her drunk and coax her into singing songs from Grease.
Even Barry's mom Michelle Harrison is a singer, although I do not see how they can make that work.
As for Candice Patton, I saw a video on Youtube of her playing Guitar Hero. I have no idea if she can sing, but I bet she is a trooper.

They all can sing I believe

Thanks for reminding me so I can remember to not watch that episode!

I remember the one from Oz. That was a good show.
"I could've sworn there was one more peanut butter left." Morgan, The Walking Dead

Thanks - I'll have to find that!
All for a box of chocolates

Yup. The episodes was called "Variety"

Oz did a musical episode??
All for a box of chocolates