dirt collected on microfleece/suede

[spiceoflife]

Silly me. I washed a picnic blanket with a nappy load. Now the linings of most of my pocket nappies and some Ai2 boosters are stained with what looks like common dirt. I washed them again in warm water, and again with a normal nappy load. Still dirty. Looks like the dirt is trapped in the microfibre by static or something. Any ideas how I can get these clean again?

[luna moth]

Bicarb might help. Otherwise, time. Just keep using them, it'll fade eventually.