So, we switched to "here's a short test, go in this room and do the test". Then we'd look at their answers. If the answers were wrong/poor we'd thank them for their time and excuse them. This way, less of our time was wasted. That test included an extremely small task like FizzBuzz. If you can't answer it you can't program, period! It filtered out the 9 out of 10 applicants who should never have applied in the first place and saved us a bunch of time.
At a big company the phone screen is supposed to do that but phone screens still take a hour or more of some engineer's time.