Mysterious tuning issue??? Fender Mex Strat

[MHoranzy]

Hey guys, hope you can help me with this one.

last night at the end of a wedding band gig, my Fender Mexican HSS strat that I’ve had for nearly 20 years decided to have all the strings drop down nearly a quarter step out of tune. I quickly returned it, and could feel that the tension was much higher. Several minutes later, it jumped back “into tune” but since I had retuned it, it was a mess again. Hard to explain. I tuned it again, but this problem happened again.

I should tell you that the tremolo is bolted and wasn’t moving around at all. Could it have been a bolt on neck thing? Anyone seen this happen before??? It was super spooky!

[mad dog]

Sounds like the neck is not tightly enough bolted down, and is shifting. Has the action changed?

[MHoranzy]

When the tuning jump happened, it did feel like the action was higher and increased tension.

[teeps]

Did it happen during a Who or Jimi Henrix act?
Joking aside, I would look at the following in some random sequence:
1. Loose nut
2. Loose neck joint
3. Truss rod dysfunctional
4. Tremolo decking. IME even a decked/blocked tremolo needs to be conveniently adjusted to be stable.
The best solution for a hardtail Strat is a hardtail Strat.

[ragman1]

I've got a mysterious out of tune issue. Might be the central heating :-)