It could be the player or the media.
You can check Samsung's web site to see if they offer a downloadable firmware update.
DVD-R or DVD+R?
DVD+R doesn't hold the DVD logo because it doesn't meet the spec's, and is not the correct medium for DVD-Video.
Also, many burner manufacturers and some burning apps offer 'Bitsetting' for DVD+R, to allow the creation of a DVD-ROM volume instead of a DVD+R volume. DVD-ROM may, in rare instances, help a DVD play on an older player, but you're still using DVD+R and it will never be a true pressed DVD-ROM.
DVD-Video should be burned on '-R' media at the slowest speed your drive is capable of, and always verify the burn with your burning software - it should be an option. These steps do create a more time-consuming process.
Also, I understand that older DVD players (I doubt this applies to your player) require the AUDIO_TS directory for compliance in DVD-Video.