Hi, if your remote is a Harmony one, could you just try (just try, you read it, right?) to install the Eversolo A6 (it's in the Harmony database) remote codes? The Z8's remote is just a little subset of the A6's one, but I am keen to thinking that the common functionalities between the two units (and their remotes) should have been coded the same... volume / input selection / eventually BT playback controls might be indeed use the same IR codes. If not, well... delete it from your handset, does not harm. HTH
No, I don't... perhaps hi-fi? audio? streamers? AV? You may ask fellow member @fofocho as he's integrated his Harmony with the A6's remote; maybe he can help you finding the correct category.
I think I searched Eversolo in media players category, but I don’t remember, or just wrote the model