Look around this forum. Your issue is common, we are all experiencing 20-40% packetloss from 9am-10pm every day. Cox is well aware, the only solution is node splits which they have neglected to do in many densely populated areas. Node splits take months to set up as they need to get construction permits with the cities and purchase equipment, etc. So the packetloss issue is not going to be solved for months.
File with the FCC as they are expecting you to pay full price for service that clearly doesn't work. Be warned, Cox reps on here are locking any post that mentions packetloss and are pointing you to a page of useless "troubleshooting" steps that tells you to power cycle your modem.
https://consumercomplaints.fcc.gov/hc/en-us/articles/115002206106-Internet-Complaints