You can buy dog silencing devices that emit ultrasonic sounds to neighbouring dogs. If I had dogs neighbouring me I certainly would give it a try.
Our neighbors have the YAPPIEST dog. It will bark for 30+ minutes at a time, often seemingly for no reason. The neighbors seem to be gone a lot, so it's possible the dog is just lonely or hungry. I feel bad for the little guy, but the shrill sounds REALLY bug me.
Fed up of being woken up at 2AM by the dog, my fiance brought out the ultrasonic anti-dog bark device he ordered from Amazon the other week. It seemed to work, but the very next day, my T (which had been stable for over 6 years) got MUCH worse. We've since turned the device off, but my T hasn't gotten better. It's almost been 2 weeks.
I'm not sure if the device caused my T increase, or if the dog barking itself did. The ironic thing is that the same night my fiance set up the device, I was sitting near the window and remember the yapping dog actually hurting my ears. (That's what got me to agree to turn on the stupid device.)
I contribute my ear issues being furthered from a loud, high pitch screaming dog next door. Did you ever attempt to record the db level with a meter? How close was the dog to where your window is? I know in a joint townhouse, our entry ways are shared and when dog comes out here he's no more than 10ft. from my window and easily hitting 95db at my window.
I feel for you, @Venusa -- although, sadly, probably not the dog's fault. Dogs bark constantly if they are bored or frightened.
We have a miniature dachshund now and for such a little guy (9 lbs), he really does have a pretty big bark. He isn't yappy but like most doxies, he barks if someone is at the door or even walking outside on the sidewalk. They're pretty territorial. Fortunately, we have impact glass so you can't hear him from outside and he doesn't bother the neighbors. Inside, it bothers my tinnitus sometimes -- but he doesn't bark that much and I love him too much to give him up.
I would never allow my dog to bark constantly and disturb others, though. We take him to outdoor restaurants and sometimes, he'll start up if there is another dog around. If he doesn't calm down, we leave. People don't pay money to eat out and listen to our dog.