Trouble with condensed instrument numbering

I hadn’t noticed before, but for some odd reason my two horns are placing their numbers differently from every other pair of instruments in this score in the condensed score.

I can’t figure out what I’m missing. They are named the same way as all the other instruments as far as I can tell.
Viola_Concerto_excerpt.dorico (1012.8 KB)

Are both horns exactly the same, eg in F (no key sig.)?

In Setup mode, try clicking on the three dots after the instrument name then Change Instrument and choosing the same “description” for both.

Did you import this file from any format?

I will have a look see.

no, it was entirely created in Dorico, though 3.5.

How hard would it be to create two new horns and copy/paste in etc?

One of the horns was created as F No Key Sig and the other as F Treble Clef Part, so they’re not identical instruments, and hence the grouping feature doesn’t kick in.

Use Change Instrument with each one to change it to the desired type of horn, and that should take care of it. (You will need to reset your custom instrument names afterwards.)

aha, thank-you.