Problem vith burned DVD-r dl

[jackcarter]

I used to burn dvd-r dl with nero and they played perfectly on my philips dvp 642 dvd player.
So I've decided to buy another Philips dvp 642 dvd player and on this one the burned dvd did not play anymore.
I have checked the two dvd players, they are virtually the sames and have both the same version of the firmware installed but on the first one, the burned double layers dvd played perfectly but on the other one, they used to freeze after 30 minutes.
I have borrowed a third philips dvp 642 (same firmware as the others) and on this one, the burned dvd also freeze.
I tried another brand of blank dvd (the first I used were philips, I changed for verbatim) : same result.
I tried another burning software (I usually copy my dvd with dvd shrink and burned them with nero, so i tried anydvd and clonedvd 2) with no more success...

If any of you could explain me why my burned dvd play wonderfully with one of my philips dvp 642 dvd player but not with an other I will be eternelly gratefull

J.C

[Krispy Kritter]

Possibly just luck. The 642 officially only supports DVD+R (not -R or DL)