ok now that we have established that indeed your DAC and Amp are working both properly we can tackle the issue of sound quality (if that;'s still concern).
What is the quality of the files you are playing and how (with which software) are you playing them?
What are you playing the music from (PC/Mac/Mobile?)?
Sometimes there is next to no difference with easy to drive headphones. So it can be totally ok if you don't hear anything special. ;-)
This is mostly true for an amp. In any case, you should be able to her quite a difference through the Wolfson WM8740 DAC on the E07k vs. your computer on any decent gear.