Depends what voice sync problems you are trying to fix.
If you are getting video drop out when capturing from your VHS tapes and that is the cause of audio sync problems after capture, then it is possible (but not guaranteed) that a TBC (which restores frame syncs for the video element) might help. I have a sort of TBC in my SVHS VCR, which makes a slight difference. A fully-featured TBC might be quite pricey - could be cheaper to get a commercial house to digitise the tapes for you.
But if the dropouts are significant, the 'cure' may not be adequate.
If there is only the occasional dropout, then you may be able to get round it on the timeline by razoring out (or overwriting with adjacent) the missing frames and re-syncing the audio manually.
If the problem isn't dropped frames, then someone might be able to offer suggestions if you describe the problem in greater detail.