Re: Zanussi washing machine model FS1555w
You could try a high temperature maintenance wash as the stuff may be sticking to soap residue on the inside surfaces. The last time I had to deal with something like this was on the older type Zanussi with a fluff filter. I had to find an old filter and cut it off, leaving just the cap. I then did lots of rinses without the filter in place to flush out the material. On yours the filter is not really a fluff filter so may not tend to get blocked so easily.