The problem is that my TB audio interface (UA Apollo X8P), was happily working but now crackles and is unusable. This works well for the external monitor - PurgeWrangler script needed to be run manually as auto-detect didn't work and got caught in a loop, but manual worked as per this post ( ) Sapphire Radeon 5700XT Nitro ('silent' BIOS and 'performance' BIOS) Thanks to this forum and PurgeWrangler, I have put together a working eGPU, as follows.
