Sometimes DOGTV stops streaming on my Roku after a few hours.

The most likely culprit is the Roku Bandwidth Saver setting. 

If the Bandwidth Saver setting is turned on, your Roku will stop streaming after 4 hours of no input from your remote.

To turn the bandwidth saver off:
Go to Settings > Network > Bandwidth saver – set to OFF

Please note, your Roku device may revert to default settings after system updates or even brief power outages.