A clarification about the codec...

BIAB uses whatever MP3 codec is installed in Windows. I remember some posts a while back on the forums about how to install a better one in Windows. I tried it with the LAME encoder and was not happy with the results for some reason. I believe the available options were a pain to access. Apparently, Microsoft makes it difficult to use anything but it's WMA - not for me. I use Foobar to convert my BIAB WAVs and, like dbPowerAmp, can choose easily what format and options I want. It's not a big deal and, actually, I prefer it.

Was the rendering problem you had due to using a soft synth instead of the UA-4FX?

R