decrease refresh accuracy

git-svn-id: http://svn.vuze.com/public/client/trunk@40248 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2
git-svn-id: http://svn.vuze.com/public/client/trunk@40250 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2
git-svn-id: http://svn.vuze.com/public/client/trunk@40251 c2c1b7af-1477-405b-86ee-8aefd1fc4dd2