Hi Nick,

I've listened to your sample and wonder if the sub is over extending. What is the sub configured as in terms of config "size". I've had similar issues and if I run size at Max it clips so I run it at size 30 with level -5db as determined by a sound meter when calibrating. The clipping only happened on a few films in certain places. When it happens can you feel the cone move a lot if you hold your hand underneath?
Just some thoughts
Bob

861v8, UHD722v2, 5200s, 5200HCSEup, M6s, 3200s, DSW, Sony 55A95L, Oppo 203, Sky Q Silver
Samsung QE43Q65B, Oppo 105 & Sky Q Mini