For people having issues with random errors i have found they flushing the redis db seems to fix them.
Provided you are not using redis for any other apps ssh into your machine and do the following which will rest most of your settings
redis-cli
The prompt will change to redis>
then type
flushall
and finally
exit
and restart
Almost forgot you will need to re run the install_miner.sh again to repopulate the db