Often while having a perfect LD a noise that is external will interrupt the dream and cause one to wake. This is because of a natural instinct to monitor the world around our sleeping body. If a dog barks in the yard, it is the natural process/instinct to wonder if the dog is near you, or even if the dog is signaling the presence of an intruder. This is an animal instinct that can be over-ridden through auto-suggestion with in the dream itself. The way you would address your dog barking while you are in an LD would be something like this. The dog barks. Your brain starts to pull out of the dream. You quickly say this and use the ability to believe you should be developing, "Oh! There is a dog in my dream! It sounds so vivid, there it is in that yard (even though you have yet to see it). I bet the dream is going to have that dog chase a cat or something. Let's just sit right hear where I can hear this dream dog for awhile. I will just take this opportunity to stabilize." With practice this kind of logic will work. I do suggest stabilizing while the sound is going on. If it continues for more than a minute or two, you should tailor the dream around the noise. Perhaps something like this, "I see, this dream is actually taking place in one of those dog parks. Well,,, there are always pretty girls walking their dogs in such a place; I will find a pretty girl walking her dog and showing her how well I can levitate." Then you can use the time to practice your levitation skills, despite a very loud barking dog outside your window.

Here is a link to a DJ entry where I use this method, 07-11-13 Sexy Tomatoes and TOTM - Dream Journals - Lucid Dreaming - Dream Views It is really long, so here is just the relevant section:

"""My mom DC pointed out water on the floor and that a fish tank must be leaking. I suddenly found the dream fading again, and stabilized by imaging I was looking at a pretzel. I ran my fingers over the little bumps of salt until the dream refocused. I was now out on my grandma’s street. I walked over by a house and intended to try growing a new tomato plant. I again caused a small branch to sprout and tried again. Darn it, tomato, not stick! I sprouted about 3 more branches. Stupid mental block.
IRL I am asleep in a cheap motel, and a stupid garbage truck is outside doing its thing. I start to become aware of the room and the stupid garbage truck. How to save this?!? I tell myself that a garbage truck is in the dream. That is what I am hearing, not a real noise,,, no reason to wake. It is a garbage truck on my grandma’s street, that is all. A garbage truck forms in the dream. A freaking noisy garbage truck. I want to maintain the dream of the garbage truck as long as it takes for the real one to finish up and leave, so I dare not shift scenes. I need the truck to be the focus of the dream, so growing tomatoes must wait.
Ah Ha! I need to hide from the garbage truck! That is the new story, and I will do so by growing one stupid branch like stick at a time and enclosing myself in a fort by forming a semi-circle against the house. Rumble rumble rumble goes the stupid garbage truck. I work away at sprouting little branch like trees (practice) until I am in a nice fort. It is actually a pretty cool enclosed area. I form a little door.
I do not know how long it took to build a fort one branch at a time, but the stupid garbage truck is still outside IRL, and I need to keep it in the dream, or wake up. What to do? Wasn’t one of Opheliablue’s TOTM to hug the first DC you see? I have already seen some, but whatever. I will use the idea, and go hug the stupid garbage truck driver. That is it, I will keep the big loud stupid truck in the dream, by going up and hugging the DC driver. At least I can have a goal and not wake up. I climb out of my little fort and walk to the street and there is the truck. I see someone in the cab. I walk towards them waving, but the truck drives away.
Yay! The stupid truck is gone IRL. I need to stabilize again, but forget what method I used. I look up and am inside a house."""

I know this is some what advancd stuff, but some of you may be ready for it. Everyone can benefit some from the general concept. Good luck and have fun dreaming!