Sometimes user try to match all discs at one time to a mutltidisc release, but often they do it one disc at a time.
if the release being matched to contains more than two discs we dont create a single matrix of songs against all tracks because can be prohibitvely expensive, instead we match the songs to one disc at a time.
But if songs are from disc 2 and we try top match to disc 1 first and it has the same number of tracks (or jmore) as songs it may allow bad match on all songs based on trackno. If all songs are deemed to have matched disc 1 we dont then try to match to disc 2, instead we break out of loop, do additional checks (such as track duration check) and only then find it is a bad match and no match is found.
We need to do the additional checks earlier and the if match fails we can discount the failing tracks and allow them to be matched to subsequent discs.
(we might also consider existing disc nos int rack metadata and if exist match to that disc first, we already do this but only if total number of tracks exceed 100)
Fixed so checks are done earlier when matching multi-disc releases to allow rechecking of badly matched tracks
Also we only do the large release search if more than 2 discs and songcount * tracksOnRelease > Threshold, otherwise we can do normal mapping whihc is most accurate. So if only matching one disc at a time likely to be below threshold, as our fairly small multidisc releases