You need to get your headphones hooked to the balanced out on A28, and depending on the headphones you might need to do it reeeeeeally badly, believe me, I got one too
A28 can be taken to a whole new level, but that's a topic well discussed on its appreciation thread.
I got D200 for the office and originally intended to use as a stand-alone unit, but that quickly changed in the last week and I think my A28 will end with at the office. They indeed pair great and so I'll have a chance to up my home system a bit.
However, kosq83 you should definitely look into utilizing A28's balanced out, just think of it this way - the amp was designed to be balanced in and out, and the 1/4" although excellent as it is has been added as a feature.