SB6190 is just a cable modem so we can check and trouble shoot the modem only by using direct connection without router. If you see the lights on the modem changing color or flashing when you loose internet you can try restarting modem or reset modem for 15-30secs without coax and check and monitor internet using direct connection for 24hrs and if still issue persist need to check the cable signal level to check the case further so please do follow the steps mentioned on the below link.

http://arris.force.com/consumers/articles/General_FAQs/SB6190-Cable-Signal-Levels

Thank you.  I’m going to reset the modem and see if that helps..  I did already check the cable signal and the numbers were all within range.

This actually just happened so I thought I’d share.  Not sure if it’s helpful or not.

I suggest you to share the cable signals to check all the signals are in range.

Also you are experiencing with intermittent connection through hardwired directly to the modem or while connecting with router.