With the MacBook Pro 2018, there can be occasional problems with sound reproduction in conjunction with professional audio equipment.
Users who use external audio interfaces report in the Apple Forum that it can happen that external devices simply lose their connection. It’s also supposed to happen that during playback noise finds its way into the playback stream. Only the 2018 MacBook Pro seems to be affected.
There are corresponding discussions in this and this forum. MOTU support is said to have pointed out that there should be fewer problems with devices connected via Thunderbolt. Mainly USB devices are affected.
As it looks, this problem seems to be limited to the newest Apple model and should be solved with an update as soon as possible. Currently it seems to be a workaround not to connect USB devices directly to the MacBook but to connect a Thunderbolt dock between them and then use the USB ports on it.
