Will the DVDs play on another player? Ideally, you should not be using the recorder as your main player.
My first DVD recorder was a Panasonic. After it wore out after years of use, I got one of those Magnavox ones that is really a Funai. Everything that I have recorded and finalized in either player plays in everything I put them in. DVD recorders are supposed to output the exact same sort of file as you would get on a commercial DVD.
The disks are finalized, but will not play on a Funai DVD player. They are the silver disks.
They seem to play OK on a Sony, not the best quality, and other Magnavox players.