Signal tap II issue

You will see this if the signals you are sampling are not synchronous to the signal tap II clock.

Basically you are sampling asynchronous signals.

This can be useful if you want to see whether there is activity on signals in another clock domain, but its not very useful for tracing synchronous activity on signals. For that, you need to make sure your signal tap II clock is the same clock as used by the logic you are tracing.

Cheers,

Dave