Trey probably switched guitars because he is playing on vintage Languedoc guitars. I play on a vintage Fender Jazz Bass and heat can reek havoc on the neck. The boys might have been road wary and the heat does not help either... long drive from LA and then really hot and humid just sucks to perform in! I have seen 178 shows since my first at Tinley Park in '93 and every musician has an off night. The boys will bounce back, they always do! Happy touring everyone!