The sound you are bothered by is sometimes called "next-fret buzz." It's the string hitting the fret above the one where it's being fretted.
The most obvious problem is that you are pulling the strings up when you pick them. That is a technique players use when they want to hear the string slapping the frets, but should not be your regular way of picking with your thumb. You can probably find some online instruction about thumb technique.
Next, if the buzz is heard all the way from the nut to the 7th fret but not above the 7th fret (your video has the capo at the sixth fret, right?) then you need more relief.
__________________
"Still a man hears what he wants to hear, and disregards the rest."
--Paul Simon
|