I just disconnected my 2021 biab audiophile SSD and re-connected my 2020 biab SSD.

I played the identical real drum track in both versions of biab. The 2020 version was clean. The 2021 version had pops.

I rendered and exported the real drum track in both versions of biab and imported them both into the same Cubase project. The 2020 version was clean. The 2021 version had pops - with 'saw-tooth' wave peaks at all the pop sites.

I am now pretty sure this is a problem with the 2021 version of biab audiophile. Whether it exists only on the SSD version or in other versions I don't know. FYI the biab style was _CLSFUNK.STY.

I will ask the PG Music boffins to look at it.