#1
So the other day I was trying to tune my A string on my acoustic up to a C for a song (Rylynn by Andy Mckee), when the tuning post kinda popped and the string went flat. I thought nothing of it and just stopped trying to tune so high. But now I'm just trying to tune back up to the A, and the tuner keeps popping/snapping/loosening(?) when just trying to tune to that.

Is there a way I can fix this?

Any help would be appreciated.
All you need is yo' fingers and the strings
#3
Did you replace the string after that happened? If not, the string simply broke. I highly doubt that you would break the tuning post before the string...