Thanks - I have switched the freehub and had the cassette off and back on during the checks to date and certainly seems well cranked down (don't actually use a torque wrench on it but "very tight" is the extent I've gone to which has never caused this issue before over the years so am fairly sure it's not that) - going by that numbering, the ones that are the cause of the issue are basically 11 - 8...!
Thanks - I have switched the freehub and had the cassette off and back on during the checks to date and certainly seems well cranked down (don't actually use a torque wrench on it but "very tight" is the extent I've gone to which has never caused this issue before over the years so am fairly sure it's not that) - going by that numbering, the ones that are the cause of the issue are basically 11 - 8...!