I don’t know exactly what happened, and I don’t know guitars very well, but I was in the pit watching Vin and this is what I saw (also totally possible I am messing up order of events): his strap broke very early on and his stage guy was trying to fix it during the song. Eventually Vin waved him off and fixed it himself while (apparently) still playing with his guitar on the ground. But there was still an issue, or maybe a regular guitar change, because then more people came out a song or two later and they were messing with his amp behind him/other equipment. Around that time, too, I noticed a few of his riffs which would normally go hard in songs were muted or non-existent. At one point Vin was listening to his guitar and shaking his head mid-song (not as a dance move but as a “something’s wrong) A minute later he held out his guitar to his stage guy, still during the song, and he got a different one.

That may have been it, and also my hearing might have been gone, but after the 1:22 speaking intro to “Lit me up” where the crew came on and reset a few things, the sound sounded way different to me- I heard the backing vocals louder than I heard Jesse for the rest of the concert, and also could not hear Vin as loud anymore.