I am having poor suction on my DC03, especially from the hose. I have checked the hose, cyclone, cassette, and no obstructions or breaks. I'm now checking the filters. The top filter came out with a bit of a struggle - I had to bend the top of the housing upwards a bit, but the lower (post-motor) filter is firmly stuck. I tried pulling it out with the plastic loop, but the loop broke off. I'm reluctant to try pulling it out with pliers for fear of damaging the connection surface. Any ideas what could be causing it to stick, and more importantly how to free it without (too much) damage?
Also the various seals are all in place but some look a bit tired, especially the round flap-valve in the cassette. It is not fully closed by about 3mm when the machine is off, but the vacuum seems to pull it closed when running. Is that normal or should I replace it?