How to boot with HIDPI custom resolution and default speaker

Hi i'm running Mac OS Mojave 10.14.1 hackintosh and basically whenever i boot into mac os i always have to manually select the speaker as my own audio device so the sound will play through it can you help me make it the default audio device right from booting. I am using Voodoo HDA 2.9.0. I also created a custom HIDPI resolution because the native 1920x1080 resolution was too tiny right now i'm using 1600x900 hidpi resolution. When i boot into mac os i always have to select it after i login with the RDM app because it doesn't show in systemspref/displays even when i click on scaled with the command button. I put the RDM app in the login items so it starts with mac os but it still does not use the hidpi resolution as default it changes to a non-hidpi 1600x900 resolution. Any help would be appreciated.