Combined bitrate ceiling for audio and video is 10.08….9.8 is video only
The problem is that most encoders aren’t very accurate on the settings you give them. Even CBR is not very constant when viewing your bitrate in an analyzer.
Its always good practice to be conservative. Id set it at around 7.7 – 8 mb/s CBR if you used AC3 audio. If you must use PCM, I d use 6.7 or so. basically you need to keep away from the 9.8 cieling….any spikes in bitrates can be an issue
VBR is used when you must allocate bitrates across a longer piece….no worries for you here.
Also, the notion that players widely balk at bitrates above 7.5 on burned media is complete BS