Hi Frogmort, Yep I was expecting a phenomenal amount of bass so you can understand my disappointment!
I've tried both the 5.1 LPCM and 5.1 TrueHD on both Blu-ray players that I own via HDMI and in every instance they behave incorrectly as described above. If I go analogue out from the BD650 to the amp the mapping is still incorrect but I do get something coming out of the sub which is VERY quiet and sounds full range from what I can tell. The seller even sent another copy and that is the same...
It is a complete mystery, any other audio disc, movie disc or file plays flawlessly as it always has so I can only conclude it is a faulty batch of discs, although I can't find anything about faulty discs on Google or on QQ. Unfortunately I haven't got a Blu-ray in my PC either so I can't even try and diagnose it that way...
I've started a return now, maybe I'll have more luck if I try and get the US version, or maybe even the DVD version if it comes to that...