I purchased a so-called "universal" DVD of an English film. The web site says it will play on US and Canadian players, implying NTSC encoding. The DVD does not play on my Panny BD-30 (the BD30's display indicated "play" but there is neither video not audio on my Panny plasma display. So far, my BD30 has played everything, at least NTSC, that I've thrown at it and, oddly, this DVD plays just fine on my Panny EH55 DVDR which may predate my BD30 (purchased February 2008) and on my really relatively old Panny DVD-RV32 SD DVD player.
Panny tech support tells me their only suggested solution is to buy a lens cleaner. Is this likely to be helpful? Are there other alternatives, perhaps accessible in the BD30's menus?