Cubase 5 "VST connexions" problem with mac outputs

Hello,
I’ve been using Cubase for 20 years now, and cubase 5 on my Mac Pro for a few years and I’ve never had this problem. I can’t find solution while looking on google on forums.
Having crackling noises on my Motu 828 mk2, I asked a sound engineer friend of mine for help to solve the problem, but as he didn’t know cubase at all, i think he may have changed some settings in “VST Connections” and maybe in “control room”…?
The problem is that I have to disconnect my Motu to get it repaired and use integrated outputs of the Mac.
Usually when I disconnected the Motu, Cubase almost “automatically” switch on the Mac outputs, or I just have to do it manually and it works.
Well, now when I select the Mac outputs in “Peripheral Set up” (i dont know if it’s the right translation from french) and I then select them outputs in “VST Connections” i have no sound at all, while Mac outputs are also selected in the “System Preferences” of the Mac pro.
When I select the Motu and I reselected its outputs etc, it works with no problem (except my motu cracklings noises problem)
What seems strange to me is that over the stereo output on the Cubase mixer, when I use the Motu, I have no indication “Motu 828” as on the other mixer’s tracks and it seems to me that there is the indication of the name of the card or outputs name above the usual hand right?
It looks like a problem of misconfigured bus but I do not see how to do better? I’ve switch off the control as i think its my friend who switch it on.
In short I am a bit annoyed because even without my Motu I can not work.
If you have an idea … Thank you in advance for your help :wink: