I have had this issue for a while now, when it comes to exporting my track to import it into another project file for mastering, I almost always get weird artifacts in various sections of the waveform.
Sometimes there is one in just the left channel in one area, then later on in the waveform there is one in the right channel.
Sometimes they occur in both channels.
When I re-render the track, the artifacts appear in different places each time.
I have nothing on the stereo out when exporting the track, and the true peak in my projects is almost always at a max of -5dB, nothing higher, so it can’t be a clipping issue.
I have tried rendering through my computer’s built-in interface and my UR22mkII, I get artifacts with both.
My buffer size is set to max when rendering.
I have tried realtime and “offline” rendering.
For information, this is my system specs:
Macbook Pro 16 Inch (2019)
Intel Core i9 8 cores
My project settings are set to 24bit and 48 kHz
For rendering, I am pretty sure that the chosen audio interface does not matter.
What exactly are those “weird artifacts”? can you hear them? If yes, can you also hear them while playback?
My first thought would actually be some plugin that does not work correctly. I’ve had a virtual instrument plugin that would playback correctly, but on render return different results, depending on whether automation was used or MIDI CC. That was simply a bug.
You didn’t write anything about what your tracks are, but if you have virtual instruments, I would go through the tedious task of sequentially soloing and exporting them to see if one of them ist the culprit. Same with any effect plugin you have somewhere in your signal path.
I can definitely hear the artifacts when I play back the rendered file in Cubase or my media player, I rewind and replay that section and it appears again, so it is in the exported waveform.
They’re like little pops or “rips”, most of the time just in one of the stereo channels and the other channel is clean.
My tracks consist mainly of virtual instruments with midi of course and audio samples.
I also send individual layers like chords, pads etc into their own labelled group, I then send those groups to their dedicated FX channels to put reverb on them for example.
As you mentioned, I fear that it is some plugin that is causing all of this. I will try to narrow it down.