Periodically losing local channels

I am using the Directv stream app on a Sony TV with Ezee fiber as the internet provider.  About once a week, the App guide won't show the local channels (e.g. below 104) so I can't access them.  (Any shows on those low number channels that I have on record still record so I can view them in My Library. ) Then about a day later, they show up again.  Now if I use an Apple TV to access Directv, I have no issues.  I have tried unplugging TV, deleting/restoring App, rebooting modem, but no luck.  I know that Sony TV is not "approved", but the App works except this hic-up.  Any ideas/help is most appreciated.  Someone else posted this issue some time ago but there was no solution that I could find.  Customer support does not have an answer.  They were supposed to have raised this issue but no answer back.