Pioneer dvr-210/310 will not play movie DVDs

Pioneer dvr-210/310 will not play movie dvds, That is pre-recorded store bought movies. The machine plays dvds that it recorded ok. When a movie dvd is loaded in the tray, the display says Loading for a miute or two, then ejects the disk. Can someone help me.

Thanks sjh3147

Hi SJH3147. My DVR-210 does the same thing, any resolution??

Thanks,
gpamp