Found my problem! It was my use of a Blackmagic capture format as I was using a BM Decklink Extreme HD card. When I specified HDV 1080i for a preset everthing worked fine playing back the timeline audio tracks through the M-Audio 1010LT.
... and did you already check the sound of the exported movie in the end?
I had the same problems, managed to get 5.1 sound in the timeline (in both PP and audition) after hours. But when I render the clips to get the movie in the end it always comes out in stereo. Mixed down to two channels. This aplies for export via Media Encoder and via Encore. NO way to get 5.1 in the end. Except with this 300$ surcode plugin, perhaps.
But I thought Encore 5.5 and PP 5.5 are able to deliver multi channel ouput. Am I wrong?
Anyone has the same problem and solved it?
My workaround was to export the audio seperately as *wav file. It perfectly got 5.1 sound. But than the problem was to join this audio file and the video file. It can't be done with PP or Encore because again they mixed it down to stereo.
5.1 is set as master channel
original clips in AVCHD 50i and 5.1 sound are played back correctly before any exporting.
realtek HD soundchip with ASIO driver
Edgar - I have the Surcode license! That is what it takes to export dd5.1.