Since the Meter Tap is completely unaware of anything else that may be present in the signal chain to which it is attached, many factors may affect the alignment of your Meter Taps when viewing them from the Meter Bridge. Due to the endless amount of permutations possible in a signal chain, from host routing to active plug-ins, a track's latency may be visible in the Meter Bridge.
There are a number of things to keep in mind which will greatly assist your Meter Taps in maintaining synchronization:
1.) Meter Taps will lose Sync over time when looping small portions of audio. If your work requires you to focus on a small portion of your timeline, setting a wider loop will result in better timing accuracy.
2.) Try to run at as low a latency as is possible.
3.) Meter Taps are at the whim of their signal chain's latency so it is best to try and place Taps in places that would have similar latencies.
4.) Meter Taps are oblivious to anything that comes after them. This means that if you place a Tap in a signal chain that has processing or volume control after the Tap, any adjustments will not be reflected in the Meter Bridge.
To address these last two issues, the ideal signal chain would be to bus the output of your tracks to separate auxiliary tracks that have only the Meter Tap in their signal chains, and whose volumes will not be altered. This will allow your DAW to take care of any potential latency issues, and will allow the Meter Taps to reflect any volume adjustments you make to each track.