hey im new to this forum. but i do have a question to ask. i got a 03 evo my reverse pops out aand grind.. so i can't reverse at all

.. i mean i can put it in reverse but wen i release the clutch to reverse it pops out and grind.. do i need a new clutch and flush my tranny fluid would that help? or do i need a new tranny? some1 help me please.. thanks ..