This has stumped me for years and I can't figure it out. But I am trying at long last to figure out what is happening. Here is one scenario.
 
Current song has 4 harmony tracks assigned to a HARMONY buss.
Each harmony track has a REVERB, CHORUS and a ECHO send.
SENDS are POST fader.
CHORUS is routed to the HARMONY buss.
REVERB is on it's own BUSS and is routed to STEREO outputs 7&8.
ECHO is on it's own BUSS and is routed to STEREO outputs 7&8.
 
If I mute any or all of the harmony tracks, Effects sends are still active.
If I pull down the faders on all of the harmony tracks, the track sends are still passing signal to the effects.
If I pull down the HARMONY buss,  effects are still being passed - though at a low level. That sort of makes sense because ECHO and REVERB faders are still up.
 
How come ?
 
 
 
I have edited this because I checked the routing and caught a error in my original post.

Ignoring the prat above, it sounds from what you've posted that everything is behaving normally.
 
You've got your Reverb & Echo on separate busses, why not do the same with the Chorus?
 
And why have you got the outputs of the Reverb & Echo Busses routed to outputs 7/8?
 
As a general rule, though most of then can be broken provided you know what you're doing, is to have your tracks routed to busses and your busses routed to the Master Buss which then goes to your interface/soundcard outs - the pairs of faders located at the extreme right hand side of the console.
 
Sends will follow a similar route - Send from Track > Buss > Master > Mains

Thanks for your reply. I send stems to my console. In other words, 7&8 go to channels 7&8 (L&R) on the console.
I do not use the Sonar master buss.

I'm confused. You have the tracks routed to the HARMONY bus, but then you also have aux sends (CHORUS) going to the same bus?
 
You're right, they should all go quiet when you mute or turn down the tracks. I'm just having difficulty picturing your routing. Where the bus outputs are routed should be irrelevant.

Yes Bit. The HARMONY "CHORUS" aux buss is routed directly to the HARMONY master buss. Makes it very easy to achieve overall level of the backgrounds after the individual track envelopes are drawn. And harmony tracks are panned about 30 % left and dedicated Chorus is panned (via it's buss) about 30 % right.
 
The same sort of thing is done with all the stems. For example all drum tracks are routed to a DRUM buss. As are any auxes inserted on drum tracks. ie: drum verb goes to a buss which have the drum verb plug inserted and drum convolution goes to it's own buss with convolution inserted. Both of those effects busses are then routed to the DRUMS master buss which is always outputted to channels one and two on the analog console.
 
Fwiw, I send stereo groups to the console which as outlined above work out as  follows in the desk:
 
Drums 1Left & 2 right.
Guitars 3Left and 4 Right
Lead vocal - Always 5 (panned hard left in Sonar which sends it to only channel 5 on the console).
Bass - Always 6 (panned hard right in Sonar which sends it to 6 in the console).
And so on.
 
These long worked out workflows and etched in stone formulas allow us to keep hardware patched on specific channels in the desk. As an  example, the LA-2a lives on analog desk channel 5 for lead vocal.
 
The Bass POD lives on analog channel 6 to help when looking for a specific tone at mix time.
The Symetrix compressor lives on Drum channels 1 and 2.
The backgrounds go to specific channels also with hardware sort of permanently patched for further external processing.
 
We have never used the Sonar master out for anything. At mix, well it's basically done, just roll tape and turn on the CD burner. We print to both at once.
 
All the these processes work very well for us. I just don't get why auxes LEAK and are not really at oo inf when post fade enabled and and a track is pulled down. Something is wrong. I have known for several years it was that way but have lived with it. Can't believe that I am the only one that has ever caught this.