I've been noticing that the meat I've been smoking has a bit of a sour taste to it. I'm wondering if this is because of the pellets I use or the mustard... I apply yellow mustard to the meat before applying rub. I smoke using PitMasters pellets mixed with a little bit of charcoal pellets from Todd in the AMNPS. I'm pretty sure it's not my rubs or the meat itself gone bad. What do you guys think?