I recorded & finalised a DVD-r (Taiyo Yuden 8x) in my Pioneer DVR-420H, which had two SP recordings on it and was dubbed at high speed, but it will not play in my Wharfedale M3 DVD Player. Other DVD-r discs, including those recorded & finalised in my previous Panasonic E95, play fine in the Wharfedale. The finalised disc plays fine on the 420H though. Is there something in the set-up of the 420H that could cause this incompatibility, or is my 420H likely to be faulty? TIA.