Our hound was a bit like you describe. She would wake up at odd hours pacing and barking. We tried the alarm clock trick and that helped a little, but what finally solved the problem was completely overhauling her feeding schedule. Even though she was receiving the correct amount of food during the day, she would wake us up at night and she was very loud about it (we happened to get a hound who likes to bark a lot, which made the sleep disruptions even worse). She just always seemed hungry! Our adoption group would tell us to stay firm and she would get used to the feeding routine, and not to worry as long as she was getting the correct amount of food. We tried that for awhile but ultimately had to make a change.
We finally bought an automatic feeder that dispenses food at pre-programmed times, including late at night and early in the morning. She gets 1 cup of food roughly every 6-7 hours for a total of 4 cups per day. This helped us tremendously. Her last meal of the day dispenses at 11:00 pm and the first will dispense in the morning at 5:30. We are usually up by 6:30 to take her out. At this point, she has learned the routine of when the food dispenses and now sleeps through the night. I think it helps that she realizes the food will appear without us, and therefore she leaves us alone.
Maybe that is worth a try?
