How Does PowerSDR v2.7.2 Map VAC1 & VAC2 With The FLEX-5000 ?

Paul, WB5AGF

(my apologia - After buying a FLEX-5000 in late 2008 I have only begun to work putting it on the air within the past few days .... so here I am working to understand a product that hasn't been made in over 2 years but it's 'new' to me. )

(I live only slightly more than 4 miles from KRLD's (50 kW on 1080 kHz) transmitting towers so it makes a pretty good test signal for certain applications.)

I have spent several hours working through the PowerSDR (v2.7.2) functions and I am coming up against a (to me) quite confusing situation with VAC1 & VAC2 (I didn't even remember installing them in my PC). My FLEX-5000 has receiver 2 installed and I have been trying to understand how receiver 1 (rx1) and receiver 2 (rx2) use VAC 1 & VAC 2 (I'm back-feeding audio to my computer using the virtual audio cables so I can use my PC's speakers and not have to keep moving the audio cable to the mini jack on the back of the FLEX-5000).

What's got me puzzled right now is that I've found that if I leave rx2 turned off then I can get audio from rx1 through either VAC1 or VAC2. It appears if the audio is taken from VAC1 then the audio output level adjustment slider (for rx1) on the PowerSDR display GUI is inoperative but if the audio comes via VAC2 then the audio output level adjustment slider works.

If I turn on rx2 then VAC2 appears to carry only its audio (if I only have VAC2 turned on then the audio output from rx1 suddenly goes silent as it loses access to VAC2 when rx2 is turned on) and for me to have audio from both rx1 and rx2 at the same time I have to have VAC1 and VAC2 both turned on as audio from rx1 will only be available from VAC1 (since rx2 appears to have complete access to VAC2 when it's active). (When rx2 is active, with its audio being carried via VAC2, its audio output level adjustment slider functions correctly.)

Let me stop here and ask ..... Have I got this much figured out correctly and (if so) why does PowerSDR v2.7.2 work this way with a FLEX-5000 ?

Then there's the question I have that has to do with the carrying capacity of the virtual audio cables .... since they can apparently 'carry' a stereo feed (else why would there be a monaural/stereo button on the VAC1 and VAC2 'tabs' in the PowerSDR set-up menu) why can't the audio from rx1 and rx2 both be carried on a single virtual audio channel (with the two audio streams either combined or with one receiver's audio on the left channel and the other receiver's audio on the right channel) ?

At this time what I'm observing appears very illogical but perhaps I have something configured incorrectly (where I couldn't guess).

- Paul, WB5AGF