I`ve seen in this video a tip to export faster: increase buffer size to maximun and decrease Volume automation precision to 1 sample.
What do you think about it? is it a good practice?
disadvantages?
Is it noticeable to modify the sample automation precision while working at 48khz and 2048 buffersize?
Can you hear an automation difference between exporting at 128 or 2048?
The whole thing with the volume automation precision in the video is a bit misleading, imho, especially if there is no volume automation present in the project (useless test…). Decreasing the precision in a project with volume automation will effectively increase your render times, as it needs more CPU. (I agree with the video through that in most cases it is probably negligible)
Increasing buffer sizes to maximum can have a some disadvantages.
First, some versions of Cubase (I tested 12) had some issues with a 2048 buffer size and rendered volume automation incorrectly at that buffer sizes . Don’t know whether that is fixed in 13.
Second, afaik practically no third party plugins supports sample accurate automation even with VST3, so the automation precision will be 2048 samples with those plugins. Whether that is noticable or not probably depends on many factors. Most plugins apply an averaging algorithm over automation data, so there will be no abrupt changes, but I wouldn’t bet on that for every plugin out there…
For example: this is the result of an steep automation of a gain control in a third party EQ plugin (Acon Digital Equalize) on a test tone. It is clear that the plugin applies some smoothing, but the result is surely different.
Whether that is important or noticable in real life situations I haven’t tested, but personally I have my buffer size permanently on 128 anyway as I am too lazy to regularly switch it back and forth 
haha me too.
I have done some tests and saw those different waveforms too, and saw worst results when a VCA track is engaged…