Fret popping up?

My acoustic guitar has developed an issue that I think may be a fret that has loosened up a little. When I play the guitar at the 12th and 13th fret the strings fret out and make a terrible sound. It's not too noticeable at the 11th fret and completely gone when I get to 14. We had an extremely hot and dry summer here, even extreme for Central Texas.

If this is a popped fret can I use a plastic mallet (gun smithing mallet) to tap the fret lightly back into place? Should I oil the fretboard before I try that? I'll be investing in a good hard case and a humidified very soon but I'd like to address this issue myself. Any thoughts?

Humidify first. Then tap it back.
The dryness has allowed the fret slots to spread. So trying to tap it back now may not work well.
Check the Stewart-MacDonald website for a fret press caul that will help you put even pressure on the fret.
You might also want to check the neck and the rest of the guitar for dryness damage.

Hope this helps,
Daniel

I haven't found any damage other than the one fret acting up. I'll have to figure out a way to humidify either that closet or the whole room. I bet my other three guitars could use it too.

My acoustic guitar has developed an issue that I think may be a fret that has loosened up a little. When I play the guitar at the 12th and 13th fret the strings fret out and make a terrible sound. It's not too noticeable at the 11th fret and completely gone when I get to 14. We had an extremely hot and dry summer here, even extreme for Central Texas.

If this is a popped fret can I use a plastic mallet (gun smithing mallet) to tap the fret lightly back into place? Should I oil the fretboard before I try that? I'll be investing in a good hard case and a humidified very soon but I'd like to address this issue myself. Any thoughts?

Don't go hammering on it, waste of time. What you need to do is squeeze the fret end back down, and wick some water-thin superglue in there. Use one of those mini-turkey baster pipettes to do this, NOT right out of the bottle.

I had a chance to play it again today for the first time in over a month and the problem is gone. It has been a lot damper here over the past six or so weeks. Could it just have been due to a lack of humidity causing it to change that much? We really did have an exceptionally dry summer.

I'll keep an eye on it and I'll pick up a case and one of those case humidifiers. Soon.

Yes, Relative humidity can affect the playability of a guitar that much. Though if you have a fret prone to escaping in dry weather, that's a problem that can be solved.

I know folks in the north east US who have a winter saddle and a summer saddle for the bridges of their acoustics. The summer saddle is a little taller and counter acts the swelling of the guitar in humid weather. The winter saddle is shorter and drops the action back down when the RH gets low. Keep in mind the difference between the two saddles is not more than 1/8" and usually about 1/16".

Daniel