Ok, Tele HH that is my main axe and true love. I've used stainless steel strings (9- 42) for decades. This axe has always had exceptional sustain and resonance but I just started to notice a slight decrease in both. My strings were getting slightly old so I slapped on a new set on and no change. This guitar has a graphite nut on it. Is it possible that process of doing minor tuning adjustments has worn a 'groove' in the nut causing a slight dampening effect? I'm noticing it mostly on the E (.009) and B (.011) strings. I do all my own setups and I haven't touched this guitar since I completed the original setup about 2 years ago... It just doesn't 'ring' and have the 'sparkle' that it used to. I've just started noticing it within the last 2-3 months. Any ideas of things I may want to check?