so i have been focusing alot on muting when play runs and the such and i have switched to muting with my thumb and i havent had a problem with it untill last night. for some reason now its like my thumb is creating feed back when im picking on the strings above where im trying to play. Could this just be a hand position issue or what im kinda miffed it also doesn't start to happen untill i play triplets at around 100bpm maybe a little faster.
Sounds to me like you're pressing in to the strings too hard; you really don't need that much in the way of pressure to stop excess noise, lighten up a little.
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