Black Box income is non-artist/recording specific income (such as audit settlement monies, unclaimed monies, leftover amounts from an unrecouped minimum guarantee, etc.) from digital music services.
This income is usually paid to AWAL based on the usage % share of AWAL's catalog on the relevant music service. We then complete a pro-rata calculation based on your performance compared to other AWAL clients on that specific service in order to calculate your share of the income.
Black Box income will be shown on your statements as an adjustment. The description will reference the source of the income, for example "Pandora AU Settlement & Advance Breakage".