Hi Pierre-Yves,
I have my BeatBuddy and Aeros connected together and haven't noticed any issue. If you only want the Aeros to receive info from the BeatBuddy, you can set the BeatBuddy MIDI out option to 'MIDI OUT' rather than MIDI MERGE or MIDI THROUGH. This means the app sends the song info to the BeatBuddy and the Beatbuddy sends the information to the Aeros looper.
Remember that if you have a song in your Aeros looper that already has a recording in a set time signature (say 4/4) and you then set the BeatBuddy to a song in 6/8, the Aeros will be annoyed!! You would need to make sure that you also load the correct song in the Aeros. The looper time signature does need to match the BeatBuddy time signature to loop correctly. If you use a song that doesn't use 4/4 timing, you will need to set the correct time in the song edit window. The default 4/4 time is only used when no value is saved for the song.
I only use the looper live and have set up a few page buttons on OpenSongApp that can control the following on the Aeros:
clear the current song
toggle the record/playback mode
load a blank freeform song (no set time signature for using the looper without the BeatBuddy)
load a blank 4/4 song (that keeps the tempo set by the BeatBuddy)
First in my MIDI chain is my guitar processor (TC Helicon VLX3). This listens on MIDI channel 1 (I usually only use a few patches, so use custom MIDI command page buttons to change these).
Next in the chain is my BeatBuddy. This listens on MIDI channel 10 and the output is set to MIDI OUT mode on MIDI channel 2
Finally in the chain is my Aeros. This listens on MIDI channel 2 and receives the BeatBuddy sync information
In OpenSongApp, I have my BeatBuddy MIDI channel set to 10 and automatically send the song information. I have my Aeros looper set to MIDI channel 2.
Hopefully this makes sense and might help with the issues you are having?
Gareth