And I'm saying, soloing a track here does not mute the send busses, nor the output busses the track is assigned to.
 
It would appear that my system is working as it should, therefore, something is wrong with yours if you are seeing something completely different happening.
 
If I solo a guitar track which has a send to both a delay and a reverb bus, I will hear a mix of guitar/delay/reverb without touching another control
 
If I just want to hear the guitar + delay, I mute the reverb bus.
If I just want to hear the reveb contribution, solo the reverb bus. This will of course pick up any other track that has a send to the reverb buss unless I also solo the guitar track
 
I think that's how it's supposed to work - it's been this way since at least Sonar 6PE and I've never questioned he functionality.
 
If you're trying to do something different, it's not apparent from your posts so a little more clarification would help

Ten to one  you guys are using the Sonar master for output to whatever you output to, if at all as it seems most people today are probably exporting. We DO NOT. We send stems to the 16 channel Lynx Aurora. Most projects have very high track counts. A short routing example,
 
Outboard console stereo channels 1&2 -  All drum tracks are always summed to these channels BUT are fed first into a Sonar DRUM buss. The individual drum tracks have sends fed to a convolution reverb DRUM VERB BUSS which in turn is also outputted to the DRUMS buss in Sonar. We do this because a great old compressor lives on these mixing console channels AND it give us the chance to do final eq touchup using the console.
 
Outboard console stereo channels 3&4 - All guitar tracks are always BUSSED to a GUITAR BUSS in Sonar. That BUSS feeds directly into Lynx channels 3&4. This  BUSS will also usually have other GUITAR EFFECTS BUSSES fed from the Sonar GUITAR tracks auxes feeding into it.
 
Lead vocal always is on track 5 and is fed to Lynx channel 5 which is in turn fed to mixing console channel 5.
 
And so on. We do a variation on mixing in the box and get the best of both worlds by using stems.
If you run the system as outlined above you might find Sonar works differently than you think.
 
FWIW, we never use the Sonar master buss, that is, the default buss that Sonar inserts for anything and consider it totally useless when using a outboard mixing console and large number of convertor channels available. The 2 channels on the Sonar default master won't do the job for us.
 

I don't see how having multiple outs or not using a master bus would cause soloed track sends to be muted.
 

That's what I was thinking Kev. 
 
Please don't talk about the cricket. 

About time you pommies got taught a thing or two about cricket. I am loving it at the moment. We are just better and that is that! Watch as we destroy you.

The subject of sport should be excluded from forums under the same umbrella as religion and politics.

As long as we keep it friendly Kev, I don't think there'll be a problem - but we are definitely getting a thumping. Series over I think.

All very friendly from this end.  But one thing is you never really know. The Brits could turn it all around. Stranger things have happened. We are on a bit of a roll at the moment and lets hope we keep on doing what we seem to be doing. I don't normally watch the cricket but I am enjoying these tests right now for sure.

We seem to making as better fist of things this morning (evening for you guys Lol)

Isn't the difference the OP is talking about is sends to busses coming from a tracks main (first) sub group don't get included in track solo.
Aux sends to busses from the track its self of course do.
I suppose it could be nice to have it both ways, and it makes for one of those up and downsides' situations to where you chain things but in general, to choose that as the SOP.. Definitely not.