lets be ridiculous and pretend it is possible to go faster than the speed of light. Any man made craft going at that speed hitting something as small as a grain of rice would explode like a nuclear bomb.
Never say never... Luddites like you have always been proven wrong.
-- Albert Einstein, German-born American physicist, 1932
It's always dangerous to say something is impossible.
That assumes that the craft itself is moving. The most probable methods of FTL involve the craft staying still, inside a bubble of warped space-time. And the BUBBLE is moved. . . but the craft never changes velocity. Hence, relativistic collisions would not be a problem.
OF course, the specific method of creating and deflating that bubble, and changing the position of the bubble, is the trifling technical details we have yet to solve. . . .
Which is why we use a Brussard ramjet.