Hi all - I’ve posted about this unit before, but I recently picked up what seemed to be a really nice 414 original Tascam portastudio. Really clean, refurbished maybe. But when I pan all the way left, the sound bumps out. As in, if I go loud with whatever I’m playing or panning, the sound distorts not unlike a bass in a massive car stereo. Doesn’t do this on the right channel. More weird - if I record and play back, the sound is not there. I tested this by playing something back on another machine. Any ideas?