So, a lot of people on head-fi seem to say that plugging an amp in through a line-out dock of an iPod/iPhone will give better results than using the headphone out. Is there any scientific basis for this claim ? In what way is the signal processed differently? Amazon reviewer SRH thinks it's better to not use an LOD: http://www.amazon.com/review/R3H4HRUK6UL5Y3/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B004QVNNI0&linkCode=&nodeID=&tag=. Are his claims correct? Also, suppose I am hooking up an amp to an Android device that doesn't have an iPod style line out dock. Would the sound quality somehow be worse? Could I hook it up through the HDMI port instead, and would this give an improvement?