I use a syringe to put reinker ink in the barrel after removing the brush tip (brush tip removal like this:
https://www.youtube.com/watch?v=t8Vv...-ts=1421782837*) (can you say 'impatient'? ;) )
My brush tips have not given my any trouble (mostly pre 2005) but the writing tip ... yi yo! if anyone has an idea about how to revive them, I'll look forward to hearing about it.)
* thanks to stamper friend tigerlily55 for sending that one my way.