Frustrated Runner

I started running in Apr 2012 and completed my first marathon 1 yr later. During this time I had various niggling injuries but nothing rest didn’t cure. After the marathon I changed footwear to a more minimalist shoe in an attempt to improve my running style. I did not experience any problems for a few months regularly running ^30 miles p/wk. Then in August during a routine 8 mile run I experienced pain in my right foot. I have rested, RICE, changed shoes (twice), undertaken numerous gait analysis (my running style is now a neutral mid/forefoot runner), visited a university sports clinic but nothing has worked. If I rest for a week the discomfort goes only to return after a couple of easy 3 mile runs. I have rested for numerous weeks and started some strength excercise too no avail. The pain is located at the front of the ankle/top of the foot and sometimes running down the inside of the ankle. The pain is never too severe that I can’t walk which makes think it is inflammation but surely this would have been resolved by the steps I’ve taken. When I run even an easy 3 miles now my right calf is tight – the left one is not.