did you recompile after this?
after recompiling
got to skill_cast_db.txt //depends if your using pre-re or re
try reducing AfterCastWalkDelay
// SkillID,CastingTime,AfterCastActDelay,AfterCastWalkDelay,Duration1,Duration2,Cool Down,Fixed Casting Time
//-- AS_SONICBLOW
136,0,0,2000,0,5000,0,-1
The aftercast Walk delay did the trick! Thanks man!