Question #1- I occasionally see videos of you guitarists setting in your studios with headphones on practicing your craft. This obviously allows for silent listening of your instrument. If you wish to practice with the aid of a backing track, music video, etc......are you using the amps "aux in" feature to add background accompaniment? You use your phone, laptop, mp3? Question #2- What do you guitarists do, if anything, to address your fingertip callouses? Mine get gnarly at times and catch on frets, sometimes also interfering with smooth string bends. You ever file them down?