Mixed Content - Secure & Non-Secure Warning

Our company just installed the latest state of the art Avaya IP phone system. I manage our remote employees who all use the Avaya Softphone for making calls. The software has a great feature that create dialable links within Internet Explorer. It highlights phone numbers in yellow, which when clicked automatically dial the number in the Avaya software. This is a huge timesaver and would greatly enhance productivity. Our sales reps average 80 - 100 calls per day.

Unfortunately, when we choose to activate that option, we get the infamous Mixed Content, Secure and Non-Secure warning which just kills NetSuite. I've tried the suggestion to "Enable" mixed content within the IE Options/Security to no avail. Nothing we've tried will get rid of the annoying and destroying warning. Does anybody have some suggestions? Upon searching the forums, I discover that there are others who experience the same problem, but it appears their concerns continue unadressed by NetSuite.