Such mistakes are not uncommon usually resulting from roon not being able to properly identify composition-related information from the tags and track titles.
Am I correct in my assumption that you are solely using tagged local files? If only one recording of a composition is originating from either a streaming service such as Oobuz or Tidal, or roon is relying on its own metadata sourced from TiVo, it might take over details from these sources regardless the user preferring data from local file tags.
If you use local tags and have set all recordings of a composition to ´multi-part compositions > prefer file info´ I recommend to doublecheck the local tags as well as the track titles:
%WORK% must be identical with all tracks belonging to one and the same composition and that one should ideally follow Tivo´s given syntax, like in Shostakovich´s case:
“Symphony No. 4 in C minor, Op. 43”
%PART% should always contain useful information and no 2 parts should ever be the same
If the composition name and the part are in the track title or filename, it should be consistent with all tracks of all recordings and not the same character should be used to separate work, movement number and movement name (which is the case here with the “-”).
I have a feeling in your case %WORK% and %PART% are either not consistent, or you have another recording of this symphony in only 3 tracks which is matching Shostakovich´s original movement nomenklatura so instead of
I - Allegretto - Presto
II - Moderato con moto
III - Largo - Allegro
roon is matching the three original movements falsely with the parts thereof, i.e. Ib and IIIa leaving two fractions of Movements I and III separated.
Apply correct %WORK% and %PART% tags and reimport that album again being set to “prefer local file tags for multi-part composition info”. It should work and look like this:
The Bruckner case is the other way round: All tracks of the 2 versions of the Symphony No. 8 seemingly bear the same %WORK% tag causing roon to think it is only one composition.
As the WAB catalogue for Bruckner does not differentiate versions of a composition, maybe you can apply a non-compliant %WORK% tag to one of the versions, like:
Symphony No. 8 in C minor, WAB 108 (edited by Haas)
which will cause roon to open a new, non-canonical composition in Bruckner´s composition list. If you later mark these 2 versions in Bruckner´s oeuvre list and merge them, the 2 recordings should appear as 2 separated ones.
Edit: Just noticing that this false merging originates from the Bruckner “The Romantic Masters” CD box and the false composition details are probably provided by TiVo, not your local tags.
There might be a workaround: Split one version of the Symphony No. 8 by using the “Fix Group tracking” apart and move it to a new album. Either the Inbal or the Barenboim recording should exist as a separated release and in this case the mixed composition should disappear.
BTW this Bruckner boxset is a nightmare regarding metadata. Would recommend to get rid of it or split it into single releases.
