Is anyone else in the cox community on a IP blacklist?

This started in May when changed my IP address. Everything was fine for a few weeks until I'm told by a website that I'm a member of that I'm using a proxy or have a tainted IP. So the suggestion from them was to change my ip again. So that whole process has led me to change my IP 5 times in the past few weeks. I think I was only able to do that is because a spammer that previously used the IPs was trying to get rid of them and now I cannot change with the luck of resetting router.

Well the reason I ask if anyone else is on the blacklist is because I've checked the IPs cox has been assigning me [ all begin with 70.185.X.X] and they are all on the blacklist. I am not a spammer/abuser so whomever had the ip before me must have done some damage.

I've checked on various websites like:

http://mxtoolbox.com/blacklists.aspx

http://whatismyipaddress.com/blacklist-check

and they say I am on a blacklist called "SORBS DUHL" which apparently have blocked the IPs for sending out spam.

That is the only blacklist I'm on. But when I searched for just numbers of random IP they have more blacklisted.

Is anyone else having this problem or it is just me?

I've contacted support and I'm not quite sure they understand my problem so I just want to know if anyone else has this as well?

I just want to know the feedback of other cox users because I find cox to be an okay ISP and I don't want to change to another company but truthfully this problem is losing me money because I work online part-time and the blacklist is causing them to think I'm on a proxy. I've used cox for about 2 years now , also changed IP before and haven't had this issue until May this year.