i'd like to perform circular recording into an array, constantly overwriting what has been recorded before. so if you put the playhead a little behind (or before - as it's circular it depends on your view) you get a simple delay. as the trigger to start recording with tabwrite~ is not sample accurate, i can't get a constant recording without clicks at the trigger points - at least not with my limited understanding of pd.
This may seem a trivial, but you should consider that regardless accuracy if there is a noticeable 'jump' from the last sample in the array and the first (meaning in this case the sample in the loop and the beginning of the loop) you would be hearing a click even with the most perfect set-up and this is likely to happen if you are filling the array live.
Regards, Lorenzo