Media for Stand-alone

I burned a couple DVD movies on this media:
RICOHJPN/R01/002 4x +R
MKM/A02/na 4x +RW

They both play on my Panasonic player, however while the +RW does play on my friend’s Sanyo 6040, the +R does not, which struck me as odd as I would more expect the reverse. So my question is whether this is likely a format compatability or a specific media incompatability and if the latter which does work? The database was unhelpful.

It could be a number of things; booktype recognition or media-type compatibility in the Sanyo…
It seems that some players just do not like certain dye types.
What writer did you use to burn the RICOH disc and at what speed?

HLG-4160 A302 @ 4x. Book type option unavailable.

I use Pioneer DVD Duplicators and use gigastorage dvd-r media and they are so fine…