I’ve had the handstick (or handheld) Dyson DC59 for about two months now, and there’s been an increasingly strange smell wafting about whenever I used it. Curiosity kills the cat but I had to figure out what that smell was. After a bit of isolation, it turned out to be the filter.
Was I not cleaning the filter correctly though? After a bit of Googling on remedies and common complaints, the answer arrived in the form of a YouTube video from Dyson.
If you notice, the top of the filter has a cap, and it can actually be removed (unclipped), just so you can run tap water directly into the filter itself. The smell was gone right after I did that, and I feel like a prize idiot now. New thing learnt, moving on!
Pretty sure this applies to all handstick non-animal vacuums (DC58 / DC59 / DC61 / DC62), so be sure to give this a try and see if it works. Alternatively, I’ve read a few tips on how a few drops of eucalyptus oil on the filter could mask the smell too.