I am having some trouble with my newly purchased Little Dot MK II. The volume knob seems like it does nothing to affect the volume or sound output really. Turning it up or down essentially makes little to no noticeable change in the tone or loudness. Connected to a PC with A/V into the amp and 3.5mm into the PC sound card (creative blaster) it sounds ok enough, I am hearing sound, but I am only able to really change the loudness with the computer's volume. It actually sounds like it picks the volume up a teeny bit if I turn the Little Dot's volume knob to zero. at 100 it seems to make it easier to start crackling and popping if I turn the PC volume up to the beginning of louder volume. It crackles and pops at a high volumes even with the Little Dot's volume at half way, if the PC volume is turned loud. I have tried it on a sony high-res mp3 player and it doesn't pop or crackle, but it doesn't go very loud at all, and once again, the volume knob on the little dot does nothing turned all the way up or down. loudness is controlled with the player, it sounds pretty good going to about a medium volume level, but just quite odd that the volume knob on the Dot does nothing. Any thoughts?