I question if this is really 2,400 lumens. And had some issues having USB flash-drives recognised if more than 32GB capacity, so anything under should be okay. And the only way I could get Audio was Not from the QKK projector built-in speakers, but using HDMI to my Laptop (playing a video), then external speakers plugged into Laptop's headphone jack...so that was also an issue. I also understand now why/how the low 'native resolution' lends itself to them saying not good for business use/presentation as the laptop screen is pretty blurry/unreadable when projected on wall. They do however get 5/5★★★★★ stars from me, for their after sales service which was excellent and gave me a solution I was happy with.