try this pattern - 1000 0010 0100 0001
Arduino pins 2 & 3 are controlling 1 winding. pins 4 and 5(Ooops - got the second set of pins wrong...) are controlling the other winding. So the motor is buzzing becase you start in one direction with pin 2 and then immediately reverse it with pin 3.
OR - try wiring it this way - Arduino -2 to LM293 -2, Arduino -3 to LM293 -10, Arduino -4 to LM293 -7, Arduino -5 to LM293 -15, and use your original output pattern.