I brought a TWSBI Go with a fine nib a while ago.
From day two it had issues with the feed drying up extremely quickly when using Diamine Scribble Purple ink.
It dried out slightly slower when using Lamy black ink but for some reason it would fling out drops of ink when uncapped or jostled (so much fun finding random ink blobs on your dark mouse mat).
Tried flushing the pen with water, taking the nib out and cleaning it with soapy water to no effect.
I was about to return the pen but I found a random post that suggested flushing the entire pen with soapy water and cleaning the nibs slit would fix the issue.
Seeing as I had nothing to loose and doing so wouldn't damage the pen I gave it a try. I ended up using some cotton sewing thread to clean the slit as that was all I had to hand.
After cleaning the pen with soapy and clean water, cleaning the nib, drying, reassembling and reinking I gave it another go.
And to my surprise it writes like a dream now and has no random ink going flying.
While I know how I went about fixing the pen wasn't the best method I thought I would post about it anyway.