A warm welcome here in the Roku Community, @Fang747!
We appreciate you reaching out for Support. No worries! We'd be more than happy to find you the best resolution possible.
Firstly, may we know what model your DVD player is? We suggest trying a different HDMI cable to connect it to your TV to see if it will make any difference. Otherwise, we highly recommend reaching out to the manufacturer of your DVD player to ask if it is compatible with your Roku TV.
Please keep us posted on how it goes!
Best regards,
Carly
Carly Y.
Roku Community Moderator