[Reece]

Try this on your sticking speaker. Sometimes over the years the cone absorbs moisture from the air and sags making the voice coil drag on the pole piece. Take the speaker out and put it on the table facing upwards. Get a little water in a cup and use your finger to carefully dampen the cone entirely. Keep water out of the voice coil area. The moisture allows the cone to move back to its original shape. Let it dry overnight sitting with the cone facing upwards. It might just get back into alignment. Have done this many times.