Well I didn't try the balanced out after disengaging the headphone amp circuit. But I would assume that the other outputs are untouched since what it does is bypasses the headphone amp. If you try to use the headphone out as a preout, you are going to get a lot of loud distortion because you are double amping the signal. When you change the jumpers, the built in headphone amp is disengaged. That way you can then use the headphone output as a line or preamp out. The volume knob still works, but at this point it's totally passive. So turning the volume all the way up is the same as lineout. There's nothing amplifying the signal any longer. And if you try to run a pair of headphones, even iems after moving the jumper, the output will be so low you could barely hear it.
So have you tried any other dacs after owning the kramer? If so, how do they compare?