IPv6 INPUT drop, IPv6 FORWARD drop, and WANATTACK drop occur several times a day

Intermittent network drops have been occurring every day for the past 6 weeks, lasting 20-30 seconds each time.  My Arris 36 (customer owned) cable modem/router is logging thousands of WANATTACK DROPs being blocked by the firewall every day, plus hundreds of IPv6 INPUT Drops and IPv6 FORWARD drops.  I have seen several other posts of this same problem, but never have I seen any solution posted.  What good is a 1000MB internet connection that drops out all the time?  very frustrated...