What version of WAAS OS are you on and how long has it been since you reset your Policy Rules to the default? Also, from enable, do a "clear connection" to purge all those out of there and get things accelerating again. The WAAS policy rules stay the same through each upgrade, so if your original policy rules date back to version 4.1.1, there have been a lot of enhancements since then.
I had a similar problem with Sophos corporate virus protection. Each of my clients would open 20+ sessions to the Sophos update server and max out my connections.
I was on WAAS OS Version 4.4.3c when it was happening. My first solution, was to create a Policy for Pass through only on the Sophos TCP port destination. I kept this policy in place until I upgraded to WAAS OS verion 5.0.1 about a month ago. After the update, I removed the rule and reset all rules to the default, which the default rule set from 5.0 is different than the default ruleset on 4.3.x which I had kept through every upgrade. I reset the ruleset for a different issue, but after I did the reset, the Sophos Clients only took 2 TCP sessions each. One from Client to Server, one from Server to Client.
Oops, just realized you are on a 522. Those can not be upgraded to 5.0.1. You can upgrade them to 4.5, if you have maintenance on it and you jump through a bunch of hoops with TAC, filling out surveys, and tons of details about your network.