There is a known feature with SNBC S80 Models where the red light will consistently flash while the printer continues to function normally. If this issue is occuring on any other SNBC models, the process is the same.

To navigate menus, press the feed button the number of times of the menu you want to access plus one.
Ex. to get to menu 3, press 4 times, with the 4th press being a hold.
Disable Paper Low Alarm
1. Put the printer in self test mode by turning the device off then holding the feed button down while turning the device back on. Press and hold Feed again to enter configuration menu.
2. Follow the steps through the configurations menus
Make sure to exit with save. Turn the printer off and on again to bring it out of self test mode.