I'm sorry to hear that you're having a problem with your unit.
Unfortunately, there not much I can do in the way of troubleshooting this particular symptom. I'd recommend calling 800-SAMSUNG to see if they can troubleshoot over the phone, or, if necessary, set up a repair ticket. The volume raising unexpectedly wouldn't be considered normal operation, and I'm not sure what to suggest.
I have the WTS1 soundbar hooked up to my 46" LED Samsung TV. It was enjoyable for one year until suddenly both remotes; Comcast AND Samsung could not control the audio. It will work for a while and then the audio will raise for no reason and neither one of the remotes can control the volume. Even if you put it down to "0", the volume will remain loud. I have had it off since May and would love to use it again. Any ideas?