I have also been looking for a good meter. Most of the "oversampled" meters I have seen on the market are pretty expensive (like $600-$1000). This is true that there can be overs between samples during D/A conversion but it can also happen with brickwall limiting. if you brickwall your music, if a peak is flat-topped, it can be reconstructed over 0dbFS. I suspect this is why some software will limit to -.1 db, but whether or not the over is audible will depend on the player and its available headroom. I also suspect that the analog side of most players are not designed to go very far over 0dbFS, and if they go over at all are probably in the "nonlinear" range anyway. Also often software will not show you what is going on behind your plugins and if you are exceeding available headroom there. it is quite possible that if you for instance have brickwalled a track and then apply eq cuts that the resulting track will go over. I know that the example given of a square wave does not seem like it matters in the "real world" but once you start limiting and/or exceeding headroom it very quickly becomes a reality, because that square wave is what you have.