To the OP - you really do have GREAT recording software, but you will need to pick up some sort of an audio interface, even a reasonable one, in order to principally take the load off of your CPU for doing the massive analog/digital conversions needed for running a program such as Sonar.
 
I happen to like using USB interfaces, and some folks choose to use FireWire types instead.
 
The low end of what I would look at starts at around $150, and will cost more if you desire more features.  The more inputs and outputs and the more mic-preamps and all of that, the more the interface will cost.
 
There are $150 interfaces that do a FINE job of meeting the needs of someone that only needs a couple of inputs - look for phantom power, and ABSOLUTELY make sure the interface supports both Windows 7 and Windows 8 with its drivers.
 
Once you DO get an audio interface, I would suggest the following configuration settings, as a reasonable starting point:
 
For the interface: Sample Rate of 48 k, ASIO Buffer Size of 128
 
For Sonar: Driver Mode of ASIO, Sample Rate of 48 k, Record Bit-Depth of 24 bits.
 
You want to run with a Sonar-reported Total Roundtrip Latency of around 10 milliseconds, or just a little less, when recording.  (for mixing, you will likely have to jack up the ASIO Buffer Size to maybe as much as 1024).
 
Bob Bone
 

Thank you, Robert and everyone for your contribution to this topic. Ultimately, the issue of some/all of my synth tracks not playing was iindeed faulted to the Audio Engine button disabling when I exited the Sonar application.
 
Throughout the day, I compiled a list of the conditions in which the Audio Engine button would disable and how I would get it working again. One of the options was to downgrade to Music Creator (which I remember was less problematic). But when I resumed the "Sonar experience", the audio engine dilemma became more erratic and inconsistent than I am capable of understanding or troubleshooting. I'm baffled and unable to convince myself that it is completely random.
 
I wrote several MIDI tracks in 1996 which I'm proud of. Obviously, things have changed since then. In July 2013, I bought with Music Creator, and a few months ago, Sonar X3 in the hopes that this little amateur music hobby would bloom into something memorable. These ten months later, I haven't finished any of my new songs because of one hiccup after another. This most recent hiccup -- erratic disabling of the Audio Engine -- has got me frustrated, lost, discouraged, confused and disappointed.
 
I have reviewed all the follow-ups herein and finally accepted the need to purchase an external audio interface. (I had seriously thought that somehow, in some way, I could accomplish this without one.) It is quite troubling how I underestimated the patience and knowledge necessary to make this work smoothly. Now I have to truly consider whether this is a hobby I'm willing to put a little more money into, let alone commit to (and believe in). However, Robert, your most recent suggestion on the audio interface is a very informative launch point, should I continue to pursue this. All the variables have just caused me to become frazzled and overwhelmed. What I feel I'm trying to pursue is similar to taking on a construction project without a college degree or proper tools.
 
I feel lost, defeated, and I don't know what to do. What if this hobby isn't meant for me? It's just fun and it feels right, and I have the creativity. I've spent so much time (although only $60) learning the Cakewalk software, experimentation and troubleshooting issues I feel incapable of handling. At the risk of eventually burning out, I may have to sideline this pursuit to recover and muster the patience and energy to resume this and take it more seriously. It may be tomorrow, it may be next week. I don't consider myself a quitter, but this is something I'll need to think over.
 
Thanks to everyone for your knowledge, input and support.

Yes it is somewhat costly but not as much as you may think. I will go out on a limb and guarantee that if you were to get a good audio interface your satisfaction quotient will increase exponentially.
 
I wouldn't let this small bump in the road stand in the way of your pursuing a music creation hobby.  A few bucks spent wisely will reap great rewards  And you never know where it will lead you. Also you may not know it now but as a member we will help you in any way we can. Its good to have this forum as a goto group.
 
Don't chuck it all over something that is so easy to fix.   

Grundberg
...finally accepted the need to purchase an external audio interface...I have to truly consider whether this is a hobby I'm willing to put a little more money into, let alone commit to...What if this hobby isn't meant for me?...

Remember that your audio interface won't just be used with Sonar. It will replace your computer's existing soundcard with something that's higher quality. It's not just about latency. Music that you listen to on YouTube, iTunes or whatever will sound better too.

@Grundberg - There are LOTS of things to learn with Sonar, or any other DAW, BUT DO NOT LET THE FRUSTRATIONS OF THE LACK OF AN AUDIO INTERFACE DETER YOU!!!!!!!
 
Please please please please please KNOW that your experience will INSTANTLY improve, when you get the settings and such together with a nice shiny new audio interface.  I have already given you some starting settings for the interface, which should simply WORK.
 
I PROMISE you that you will get WAY more enjoyment out of it all, once you get to the magical place of it all simply working.
 
I am a NEWBIE, when it comes to mixing and mastering, and despite having Cakewalk products for 20+ years, there are STILL lots of things for me to know.  BUT, all I have to do is fire up Sonar, and I can record to my heart's content, and Sonar doesn't crash, and things record and playback, and I CAN get complete bliss from being able to express myself through my music.
 
I TRULY believe you will have a fabulous, life changing experience once things get stabilized with having the right gear - you already have a capable computer, and Sonar is certainly up to the job, all you are missing is the audio interface.  REALLY.
 
ON TOP OF ALL OF THAT, you have this wonderful and helpful forum, FULL of folks who will bend over backward to assist you.
 
I PROMISE my support to you, as long as you remain engaged in the process and are willing to work with those who are seeking to assist you.
 
You are like 90% there - maybe more.  You do not need to start with a $500 interface.  Look at one of the $150-$200 ones.  IF you outgrow that at some point, you can always sell it and move up to something more elaborate, but in the meantime, you will STILL have tons of fun, because once it is set up, things just work.  Yes, there will be updates, and OS maintenance, and learning curve, but that is a small part of the whole experience.
 
Bob Bone
 
 
 

what is it that mc6 can't do that sonar can? did you try the asio4all driver for the onboard soundcard?

I'm sorry lawp but that is bad advice and not a good road for this person to go down. asio4all is just a band-aid solution for desperate people who just  want to do some editing while using a laptop. It is a very weak "heart" for an well oiled audio system. 
 
This long winded thread could have had 3 posts and one paragraph, 
You start all troubleshooting by asking if the OP has a up to date Audio Driver and a proper interface. If it is not in the signature, ask. 

Personally I've had great results with asio4all, better to regret something you have done than something you haven't ;-)

John

Yes it is somewhat costly but not as much as you may think. I will go out on a limb and guarantee that if you were to get a good audio interface your satisfaction quotient will increase exponentially.

I wouldn't let this small bump in the road stand in the way of your pursuing a music creation hobby.  A few bucks spent wisely will reap great rewards  And you never know where it will lead you. Also you may not know it now but as a member we will help you in any way we can. Its good to have this forum as a goto group.

Thank you for those thoughts. I completely agree but I simply was either stubborn or set on doing this work without the interface.

robert_e_bone
Please please please please please KNOW that your experience will INSTANTLY improve, when you get the settings and such together with a nice shiny new audio interface.  I have already given you some starting settings for the interface, which should simply WORK.

I TRULY believe you will have a fabulous, life changing experience once things get stabilized with having the right gear - you already have a capable computer, and Sonar is certainly up to the job, all you are missing is the audio interface.  REALLY.

ON TOP OF ALL OF THAT, you have this wonderful and helpful forum, FULL of folks who will bend over backward to assist you. I PROMISE my support to you, as long as you remain engaged in the process and are willing to work with those who are seeking to assist you.

You have been a tremendous help in offering your time to test my template for me. That being said -- leaving the audio interface out of the equation for a moment -- I've made another discovery pertaining to the audio engine button...! (See very bottom.)

Kev999
Remember that your audio interface won't just be used with Sonar. It will replace your computer's existing soundcard with something that's higher quality. It's not just about latency. Music that you listen to on YouTube, iTunes or whatever will sound better too.

I can understand that. GuitarHacker (over at the Music Creator Forum) was the first person to suggest an audio interface back in July when I first started with Cakewalk software. I'm convinced that this investment would help if I went forward with that.
 

Cactus Music
This long winded thread could have had 3 posts and one paragraph,

You start all troubleshooting by asking if the OP has a up to date Audio Driver and a proper interface. If it is not in the signature, ask.

I'm going to close this thread here. As of today, the problem has resolved itself twice throughout the conversation.

If I may, please allow me to inject one more discovery (putting the audio interface out of the equation for a moment) pertaining to the Audio Engine button. I've started a new thread, briefly summarizing the issue and outlining my discovery (and intentions forthcoming).

Please see here:
"[RESOLVED] Audio Engine button disabling / Audio interface questions"

ASIO4all... Just don't :)