I had a similar problem, the audio started playing on the empty part of the track. I have a one minute gap between two aiff files on the same track, it would start playing the first file during the gap. I had to use the mute automation in between files.
I purchased the LG 12x Blu-Ray burner. Don’t let the windows compatable throw you, it works fine with Mac. I use it with my MacPro, MacBook Pro and the IMac at my church. I only used Verbatim and Sony Blu-Ray disk.