The fan is/seems to be running at fixed speed, so silent means : remove fan (see page 1 for instructions, easy just unscrew and unlock the connector).
Then there is no noise whatsoever. But to avoid problems with heat, you should go down to the lowest frequency setting (384Mhz, you define this in the startup bat file, see page 1), AND trim down core voltage. You would do that with the fan on first, i.e., define clockfrequency at 384, turn down core as much as it goes with keeping hardware errors < 1-2%, you may even tweak down a bit mem voltage too. Once that's ok, remove the fan and it will be completely silent. You can run this directly from any PC USB port. With one MLD at 384Mhz the hashrate will be 2.2Mh/s, that won't give you much of a return though. To be precise 0.07$/day at current difficulty and LTC value.

Are there any recommended voltage settings for a macbook pro usb port? (Might be the same for any laptop)

I will only run one ML2


It might be cool to collect settings for common setups. ex:

 - Macbook Pro
 - Regular Windows laptop
 - ..