Hmmm..arrow spine could be the culprit, but I'm not so sure.. I shot 45/60s out of my Pro 40 dual cam (60 pounds/29") with no issues, but I was shooting vanes and a 27.25" arrow. The Justice doesn't store nearly as much energy, but the nock travel usually requires a stiffer shaft.

An inexpensive test would be to try some 75 grain points, fletch with vanes, or drop bow weight one to two turns and see what happens.... then you can pinpoint a spine problem.