I use track stacks to group sections of my mix. i.e. drums stack, guitars stack etc. My FX auxes receive audio from various tracks within the aforementioned stacks. Now I like soloing my FX auxes when processing returns as this allows me to better hear any offending frequencies or buildups. The problem is, the moment I solo any FX aux I hear no audio and the meters aren't lit up, which means there's no sound reaching the aux. If I go ahead and flatten all the track stacks, then I'm able to solo an FX aux and hear just return. I love working with stacks as they make the work area a lot cleaner and organised, but this one issue is preventing me from using them. Does anyone know how to fix this?