For owned trailers or unsupported third-party mods, the developer included a manual workaround via the menu: Navigate to Audio Settings .
: Adds a constant engine hum that is audible both outside the trailer and from within the truck cabin. REEFER TRAILER SOUND ADDON V1.0.8 1.46
Select from the voice navigation dropdown. Click Preview (this activates the sound in the background). For owned trailers or unsupported third-party mods, the
: Includes multiple reefer engine variations that change depending on the trailer model being used. REEFER TRAILER SOUND ADDON V1.0.8 1.46
: Using the "Force enable" workaround does not support the initial startup and beep sound effects.