give more information about your card. what are the temperatures? after you notice it and restart the rig, does everything work normally then?
You can enable scheduled restart if the miner had a low hashrate (you will see in the log how many outs the restarted machine is).
Post here more info, but you can try to reduce overclock or even get back to stock settings and test for a few hours.
Don't do any changes with the miner working, pause first, change the settings and then restart the miner or even reboot and let it running
Sometimes I changed everything with miner running, and I had some errors too
Usually, I do one change per restart. so it is easier for me to follow the result of the change.