The DirectShow filter would need to support S/pdif output. As far as I know none does at the moment. You can try bugging the CoreAAC people if you want ;). Do you have an AAC supporting hardware device?
Kpex: No, I don't have a AAC supporting hardware device as far I know :( DIggedy: Sad thing but I don't have an optical out either :( I'll just have to pray real hard that they support it in the near future, thx for ur help.
--------------------- The older the boy, the bigger the toy!
Maybe we should keep track of MatrixMixer. It doesn't support SPDIF passthrough yet, but it's not far from that. AC3Filter (its brother project) does the passthrough.