I'm working for a company that sells hosted CRM services, and as such we send a ton of email. We've done a lot of work over the past few years to tighten up the way we send email [double opt-in, bounce tracking, FBL processing, client education, etc] and our reputation has been relatively fine.
However, we recently migrated to a new batch of hardware with new IPs and have found that Cox is permanently deferring our email with a CXBL response. We've tried contacting Cox through their postmaster form several times over the past weeks, but have not received any response.
Now I've not seen anything ominous in either abuse reports or FBL messages for our relays, so I don't think we have a rogue/hacked client sending out spam, and the traffic ramp-up from these new relay IPs should have happened over the course of a month. I've also run the IPs through a thorough blacklist check to make sure we didn't inherit someone else's problem.
I simply cannot understand why Cox refuses to contact us regarding this issue. Does anyone have some advice on how to get through to them? Is there a phone number for their email admins or a secret phrase I need to slip into my next email?