How you power the Fiio E7 will always affect the sound. Clean sound and good power supplies are hard to come by these days. I do not think it is about "handling the signal better". It is probably a sheer power issue. The Fiio needs a certain amount of clean power to achieve peak performance and your desktop, as you mentioned, delivers.
The $2 option
First try an AC to USB power device so you can use a wall plug to power the Fiio E7. This should cure the problem altogether as the wall will be supplying the power rather than your laptop. You can find these at a local electronics store or the link below.
http://www.amazon.com/gp/product/B000A2BLEC/ref=pd_lpo_k2_dp_sr_2?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B000HGKF34&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0N0K4RYV49QYJH4RNZPV
The $114 Option
The Fiio E9 will charge your E7 and can be externally powered. It may be an inexpensive option for you.
The $150 option and last resort
My last suggestion would be to try a Total Bithead and see if you like it better. Headphone.com sells them and has a 30 day return policy so if you do not like it or do not find that it solves this issue then you can just return it. I would really recommend that you need an externally powered amp/DAC. This will take the power consumption away from the computer and solely depend upon where you are plugging it in. This will probably increase the cost of your setup though because you will now need a different amp / DAC.
Perhaps someone else will chime in here and let you know if the Fiio E9 is worth it. In the end I would ask yourself weather or not the audible change is worth spending more money? Most of us aim for improvement so I feel you there, but if the difference is only noticeable when you A/B compare the two then perhaps you will never notice while you listen to your laptop.
Best of luck.
Edited by NA Blur - 9/4/11 at 6:04pm
