Occasionally, and it seems to be growing more frequent, a track will turn grey. From there on, anytime I attempt to do anything with that track, Sonar will freeze and I will have to shut it down in the task manager. It looks like: 
I'm not sure what I'm doing to cause this. Does anyone have any input?
 
I'm running Sonar Platinum on Intel Core(TM) i7-4790 CPU @ 3.60 HZ with 16 GB RAM 64 bit windows 10

Usually a greyed out clip means that it is muted.

The other explanation is that the view for that track has switched from Clips to something else (eg. Automation).

what kind of soundcard are you using ?
what are you doing previous to this happening ?
what plug ins are you using ?

I just experienced this last night.  It was not muted and in fact I could mute and unmute the track but it wouldn't return to "normal."  I tried switching from different track views.  I had one instance of Izotope Nectar inserted.  Tried toggling that on/off, tried bypassing the bin entirely.  Nothing worked.  I didn't want to remove Nectar because I had it set the way I wanted (in retrospect I could have saved it as a preset and removed it, but I had grown frustrated and wasn't thinking correctly). All the other tracks in the song worked fine, but this one would not play.  It's as if it was muted--but I know it wasn't.  
 
I closed the project and re-opened and the track was fine.
 
I wish I had more to tell you.
 
EDIT:  Win10, 16GB RAM, i7-2700k, Focusrite Saffire Pro 40 w/ OctaPre
EDIT:  I also tried muting and unmuting the clip and that didn't work either.

chuckebaby
what kind of soundcard are you using ?
what are you doing previous to this happening ?
what plug ins are you using ?

- Scarlett Focusrite 2i2
- It seems that anytime this has happened, right before it, I was copying and pasting a clip, or notes, to and from that track.
- In the example, I have once instance of Breverb loaded on the affected track. I'm not sure about previous times this has happened. I've fixed the issue in the past by manually creating a new track, and then manually entering all parameters and notes. 

vanblah
  It's as if it was muted--but I know it wasn't.  
 

Yeah, it looks like it's muted, but as long as I don't touch the track, it still plays. It's just that, as soon as I try to do anything at all to the track, Sonar freezes. 
 

vanblah
 I closed the project and re-opened and the track was fine.
 

 
This worked the first couple of times it happened, but now it appears even after closing out the program and reopening. 

OK. In the project in the example, I just tried bypassing Breverb, and then unbypassing. Now, everything's back to normal. I still don't know what happened, but when the issue arises again, I'll try that again and come back to this thread to say whether it worked or not.  

When (if) this happens again could you take another screencap with the Track expanded vertically more and maybe a second one with Take Lanes opened?
 
I'm assuming you are copying data straight into the Parent Tracl (the "clip" shown is actually a composite of the clips in the Take Lanes).
 
What MAY be happening is that as you add/remove/manipulate data in the Parent Track it creating a bunch of clips in the Take Lanes area. Sometimes when working this way Sonar chokes on itself because it's trying do all this wacky stuff with the clips inside the Lanes that you wouldn't see with them closed.
 
Actually just open up the Take Lanes to see if there is some crazy mess going on. If so you can probably just bounce all the useable clips into one clip, double check to make sure that the clip is indeed what you want then delete everything else. From that point forward instead of using the Parent Track to manipulate your MIDI Clip (SS Clip or whatever) keep that one lane open and make all your adjustments to that one clip.
 
Sorry if that doesn't make a lot of sense or isn't the problem but yeah... I think you've got a case of "Parent Track-itus".
 
Cheers.

Beepster
When (if) this happens again could you take another screencap with the Track expanded vertically more and maybe a second one with Take Lanes opened?
 
I'm assuming you are copying data straight into the Parent Tracl (the "clip" shown is actually a composite of the clips in the Take Lanes).
 
What MAY be happening is that as you add/remove/manipulate data in the Parent Track it creating a bunch of clips in the Take Lanes area. Sometimes when working this way Sonar chokes on itself because it's trying do all this wacky stuff with the clips inside the Lanes that you wouldn't see with them closed.
 
Actually just open up the Take Lanes to see if there is some crazy mess going on. If so you can probably just bounce all the useable clips into one clip, double check to make sure that the clip is indeed what you want then delete everything else. From that point forward instead of using the Parent Track to manipulate your MIDI Clip (SS Clip or whatever) keep that one lane open and make all your adjustments to that one clip.
 
Sorry if that doesn't make a lot of sense or isn't the problem but yeah... I think you've got a case of "Parent Track-itus".
 
Cheers.

I think you may have it. I looked at the take lanes and the affected track has one extra take lane compared to the others. I hadn't thought of take lanes, because I had recently started the project, and had manually entered most of the notes. Now that I did the digging, I've realized that I armed the piano track, and played a small piece on the keyboard, which I had forgotten about, and then stared slicing and dicing that part and copying and pasting. So, when I actually played that one small part, it probably started using the take lanes. 
 
I'm still not sure why bypassing and then unbypassing the Breverb fixed it.