There's not much dirt etc. inside, certainly nothing that could be clogging it up in the main part.
The only thing is, the wet/dry cylinder which is on the outside of the unit, has lots of dirt etc. stuck to it, and this moves up and down. I guess this could be clogging it up and preventing it from moving up and down at times?
In the manual, it says never to open the chamber of the wet/dry though - does anyone have one of these filters could could help me get rid of this buzzing and perhaps clean the filter without destroying all of the bacteria? Occasionally, the filter will make a VERY loud sucking noise for like an hour, then stop and be ok again. So much so that it sounds like the filter has stopped working - but then it's absolutely fine again.
Can anyone help? I'm concerned the filter could stop working all of a sudden.