Hi,
(Sorry for this long writeup... seemed necessary)  I'm using an hdsp 9652 card with Jack on Linux (AV Linux), connected to a Frontier Tango24 D/A.  The Tango24 has 8 ADAT outputs, but I needed 10 output channels, so I configured the hdsp spdif for optical output to get 2 more channels.  (I like the optical output, 'cause my computer seems to make a lot of noise and the optical isolation gets rid of it.)  So my 8 hdsp outputs show up on hdsp channels 9 thru 16 and go to adat2, and I write to hdsp spdif channels 25 & 26 and it goes out to optical adat1, connecting to a little 2 channel Orei spdif unit and then to an amp for rear surround channels.  It has all been working reasonably well.

I just worked on my system and made it use all 6 channels of 5.1 surround sound, so now I have LFE coming in to Jack thru the PulseAudio sink.  I see the 6 channels in the PA sink, and I connect them to my Ecasound chainsetup and process them (speaker crossovers & such), then send them out to Jack, which connects to the RME 9652.  I connect 8 Ecasound output channels to Jack system channels 9 thru 16, and the last 2 Ecasound channels (for rear surround) connect to Jack system channels 25 & 26.

THE PROBLEM:  The LFE output, which I send to subwoofers on adat2 on channels 9 and 10, also shows up on the spdif output (which happens to be connected to my rear surround speakers).  I've tried a lot of things in my Ecasound chain setup, and no matter how simple I make it, this is always happening; the signals on channels 9 & 10 also go to spdif (which is on channels 25 and 26).  I see them right there on hdspmixer.  I don't really want these low sounds going to my fairly small rear speakers... 

This might be a hint as to what is wrong:  when I use speaker-test on the LFE channel, and watch hdspmixer, I see the bar graphs go up on the playback view, on SP.L AND SP.R, at the same time I see output on A2.1 and A2.2.  And I see the graph go up on Out 9 and Out 10 of the output view, as it should.  But I don't see any output on the output view bar graphs for Out 25 and Out 26, which is right I think since I'm not sending anything to 25 and 26 via Jack.  When I use speaker-test to send a signal to the rear channels, I DO see output on Out 25/26 (as well as on SP.L and SP.R), just like I should.  This really makes me think there's nothing wrong in Ecasound, and something is getting routed incorrectly in the HDSP.  But I have not really done any routing for the HDSP, other than setting it to use ADAT1 for spdif.  Maybe I need to explicitly set up some routing info in a config file, to keep this from happening?

Have worked hard on this, kinda tearing my hair out at this point...  Any ideas what I'm doing wrong?
Thanks!!
John