I have a somewhat complex mouth structure (my animation, not me personally). It has an 'upper switch layer' that can choose between a mouth that does lip syncing based on either volume or phonemes. Both the phoneme and volume layers are also switch layers (or course), one with phoneme layers, the other with a volume mouth with 49 different sized openings for different volume layers. I've made sure, all layers are set to visible.
I then create a simple animation like so. I set it up so at frame 1 the upper switch layer is set to the volume mouth and its layer set to volume 0 (the one at the bottom of the volume layer list).
I then import an audio file of my voice at frame 24. I then tell the volume layer to use the audio file for lip syncing (no interpolation).
It builds the switch layer, I play it, it looks perfect. Total frames is 1980.
I then export it to a quick time move at highest quality. It renders, apparently just fine.
I then play it back. At two locations there are black frames! I've removed them at one location, it was like 2 or 3 frames of just black. Nothing special going on.
This may not be relevant, but it seems it did it on a frame where it specifically called out the zero volume layer (i.e., it set up a key-frame setting that frame to use the volume zero layer). It was this frame and either 1 or 2 frame more it went black. Though it does this (set it to volume layer 0) in many places where no problem occurs.
My video has two locations these black frames occur. Other than that, it is perfect.
This is ok for my test. But hate to remove frames, it can kill critical timing... and if those frames aren't quiet, it would be bad...
I can provide the materials to make this happen (though the voice file is big), if desired. But if this is already a known problem (couldn't find it in search, but i might have not searched 'correctly') then just point me to a solution or an acknowledgment it needs fixing...
BTW: AS7PRO is the version, system win 7 home premium, 64-bit, 8-core, 8G RAM