PrimoBurnerSDK 3.5.6 introduced a new way for writing hidden tracks to audio CDs.
Before 3.5.6 there would always be a digital silence of 2 seconds at the start of the pre-gap on the first track.
Now PrimoBurner allows the first two seconds to be filled with audio too. All that needs to be done is to set the pre-gap start of the first track to -150. The following code shows how you can use the new feature:
While PrimoBurner enforces a minimum pre-gap of 2 seconds at the beginning of an audio session, there is no restriction for the maximum length of the pre-gap, so it is possible to place an arbitrary audio content in the pre-gap of the first track.
Such a layout will create a CD with the a “hidden track”. It is “hidden” because normally the only way to play it is by manually seeking to before the start of the first track.