Hi there! I see you're having trouble connecting to your Cambridge Audio Evo 75 via Qobuz Connect on your Mac, but AirPlay works fine. Let’s try to get this sorted out for you.

First, just to make sure, can you confirm if your Qobuz app is up to date on your Mac? Sometimes compatibility improvements are included in updates.

Assuming it is updated, here’s a step-by-step approach to troubleshoot the connection issue:

1. Check Network Connection:
Ensure that your Cambridge Audio Evo 75 and your Mac are connected to the same Wi-Fi network. Qobuz Connect relies on both devices being on the same network to discover each other.

2. Restart Devices:
Try turning off and on both your Cambridge Audio Evo 75 and your Mac. This can often clear any temporary glitches.

3. Enable Qobuz Connect Properly:
In the Qobuz app on your Mac, select the playback device icon and look for your Evo 75 under Qobuz Connect devices. Sometimes it takes a moment to appear.

4. Disable Other Streaming Protocols Temporarily:
Since AirPlay is working, but Connect is not, disable AirPlay or other casting apps temporarily to avoid conflicts during this test.

5. Update Firmware on Evo 75:
Check if your Cambridge Audio Evo 75’s firmware is the latest version. An outdated firmware can cause connectivity problems.

6. Verify Compatibility:
Your Evo 75 supports Qobuz Connect, but double-check in the Qobuz device compatibility list online or in the Cambridge Audio support pages to be sure.

If after these steps you still can’t connect, this might be related to the current partial compatibility between Qobuz app and certain network streaming protocols on the Evo series, as a few other users have mentioned that casting may default to AirPlay or be limited in bit depth1.

To go further:

- You might want to try logging out and back into the Qobuz app to refresh your session.
- Consider reinstalling the Qobuz app on your Mac.
- Also, check the Cambridge Audio support FAQs for any known issues or patches regarding Qobuz Connect5.

If none of this resolves the issue, I’d be happy to assist you with more advanced diagnostics or suggest contacting Cambridge Audio support for firmware-specific advice.

Does this help, or have you tried some of these steps already?