I have used this successfully for 10 years, then last year following a routine service it now uses a full cassette of thread in 10-15 mins max, same mixed ground conditions as always. I have replaced the cassette for a new Stihl one, use correct spec Stihl line, thread it as I always have, and have sharpened the line length trimmer in plastic head-guard. I'm wondering if maybe it's now running quicker and hence sending the line out wrongly, otherwise I have no idea and after all the years of being the best unit ever I'm thinking I may need to go to another brand. Any ideas?