Project Manager / Render and replace don't work on 5.1 + Stereo audio channel configuration.

Hi there, 

I have been experiencing this issue/bug using ''Project Manager'' and ''Render and Replace'' for a while, not knowing exactly what caused the issue. 

Diggin into it a bit more I realised that the cause was a specific combination of Audio multi channel configuration.

The issue:

With some Apple Prores files, both 'Project Manager'' and ''Render and Replace'' just don't work.
The rendering process starts but and an error message pops up saying ''Unable to match audio channes''

In this case, the audio configuration is a multi channel 5.1 + 2.0 stereo. (8channels total)

I tried many conbination of codecs and rendering presets, even matching the same audio configuration 5.1+2.0 using a custom rendering preset, it didn't work.

With rendering preset with audio disabled in the rendering settings, still doesn't work.

(I want to point out that this does't matter for any other multichannel file. Usually is able to match the audio configuration of any give file regardless the rendering preset you use with Render and Replace or Project manager)

Also, Render and replace (which doesn't export audio at all in the first place) gives the same error ''Unable to match audio channes'' which it's quite silly to me. 

Clearly this is a BUG that appears when there are mixed audio channels (mono+stereo - 5.1+stereo + etc...)

Can I expect this bug get sorted at some point?
Is there a workaround that doesn't require to rewrap the original source from 5.1+Stereo to 8 Mono Channels?

This is working but it's not an accettable workaround for us. 
Somethimes we are working with hundreads of files like this in a give project and I don't like to idea of re-wrapping the source because of a software bug. 

Thanks for the help,
Marco.