I was a bit non-plussed when the concert band rehearsal started this evening and I could hear that my tuning was off. I was having to bend up my notes across all strings to get them in pitch with the rest of the band. I wondered if the warm room was setting all my fellow players off but, as soon as I got a short rest, I checked my tuner and saw that it had somehow got jogged to 434Hz! I was able to get back to 440Hz as the reference and my strings in tune but it threw me out for a bit!

I was about 1/8th tone out but at least I heard it. I wonder how small the discrepancy could get before I stopped noticing? Probably not an experiment to try out in a rehearsal though.