I first purchased the CAX30 over a year ago and still have yet to find a solid fix for the problem

SO your getting some correctables. Means the modem is taking care of data ok. Usually those would be all zeros. Something you might look into with the ISP. Sometimes those can be solved by checking cabling, connections and no splitters on the line. 

If you live in a apt complex, reduce the transmit power on both radios from 100% to try 50% first...maybe 25% if your in a small sized apt area. This will help with interferences from neighboring wifi signals. 

Much can be done with wireless head phones that work on same frequency. I ran in to this on xbox360 years ago. Went wired and never looked back.