are there any receivers with line-level audio out?

The Yahama RX-A3020 supports HMDI, SPDIF and analogue inputs for the zone 2 pre-outs. Certain 2011 and earlier Denon receivers support SDPIF and analogue inputs for the zone 2 and 3 pre-outs. These zone pre-outs can be set a fixed volume and so can act as normal line-level outputs.

The simplest solution would be to hook up your sources using analogue audio cables as well digital ones.

The Onkyo TX-NR-717 has analog outputs for all 7 channels.

Those are pre-outs on the TX-NR717. Plenty of higher end receivers have them, and all receivers have analogue speaker level outputs for that matter, but they're affected by the recevier's volume control and bass management so they may not be suitable for what airdrummer is trying to do.

While the VSX-920 should by default select the digital audio input jack over the analogue audio input jacks for a given input, this only applies to the speaker outputs. For the receiver's line level audio output it will always select the analogue audio input jacks because it's not capable of selecting the digital ones.

If you're not getting anything out of the line level audio output with the source hooked up by analogue audio cables as well then the problem is likely that your source doesn't simultaneously output digital and analogue audio. You probably need to select one or the other with your Mac mini.

Even with a stereo input? You'd think it would pass that through . . . But not too sruprising ifa switcher can't decode multichannel then mix it down to stereo, as that exceeds the concept of "switch." And having once improperly connected my center, I can tell you that listening to just th Land R of a multichannel mix is pretty useless, unless you just don't like to be bothered by all those people talking all the time in a movie . . .

My Harman/Kardon AVR230 outputs on 6.1 analog channels even when a digital sound source is used, I don't know if this is true for their newer HK HDMI receivers, but I have no problems even tho all my inputs are digital. I don't even run any speakers off the 230, I use it's pre-amp outs to distribute FL/SR/SB/C/SW to separate amps pushing Kilpsch F-series speakers, it sounds fantastic. I am going to be upgrading it this weekend to an AVR245 I just scored on ebay so I can have 7.1, HDMI and Dolby PIIx's features, I'll let you know if it distributes HDMI as well then.
Edited by kvining - 1/3/13 at 11:06am

Again those are pre-outs on the HK AVR 620. Any receiver with pre-outs supports using any kind of input, analogue or digital, with the pre-outs, just like they support any kind of input with their speaker outputs.

I am assuming that after the signal comes into the HK230's optical port ( which I set up to come in as an unencoded bitstream on the source device) , then the HK's DAC converts each channel based on the selected protocol and then selects the proper analog port to send it through, correct? For example, I select Dolby PLIIx, that is essentially the sound format that is going to be sent to the amps via analog by the HK if I set it up to decode on the receiver. Sure sounds like that is what I am getting. I'm getting killer movie surround and for the most part, excellent psuedo-5.1 channel from my old stereo CDs and killer SACD.

The signal the that gets output from an AV receiver's pre-outs is exact same signal that gets output from the AV recevier's speaker terminals except that it hasn't been amplified to speaker levels. Internally after all decoding and processing has been applied, the same signal get split into two and gets sent both to the receiver's own internal power amps and the pre-out jacks.

So perhaps the switch woulld output stereo if you wet the sourcec device to output stereo so it has a stereo signall to process