kingmona , remove the batteries from remote, if volume still fluctuates you have ruled out the remote. Unplug TV, remove the back off the TV locate where the on board volume control is and unplug it. Re install the back, plug in and try TV, use the remote to control TV and if volume has stopped fluctuating, it is that manual control button/board that is the issue. In forums they state this may be a common problem in older Samsung. Good luck.
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