[BUG] Loopback endpoints specified in midi config file cause service to crash on startup (DP8)

[Psychlist1972]

Due to a race condition with initialization, specifying loopback endpoints in the midiconfig json will cause the service to crash on startup.

Repro

update the default.midiconfig.json file (assuming that is the current config file specified in the registry) in %allusersprofile%\Microsoft\MIDI (will require permissions changes in current Canary releases) with the following:

        "{942BF02D-93C0-4EA8-B03E-D51156CA75E1}":
        {
            "_comment": "Loopback Endpoint Pairs",
            "create":
            {
                "{f2e50be3-b43e-4d5b-abab-0e0e633888a3}":
                {
                    "endpointA":
                    {
                        "name": "Loopback Endpoint A",
                        "description": "A loopback endpoint created from the config file.",
                        "uniqueIdentifier" : "5150-OU812-PMB-A"
                    },
                    "endpointB":
                    {
                        "name": "Loopback Endpoint B",
                        "description": "A loopback endpoint created from the config file.",
                        "uniqueIdentifier" : "5150-OU812-PMB-B"
                    }
                }
            }
        },

(ensure you replace the contents of the existing Loopback GUID section and do not create a duplicate section)

Restart the service. It will fail to start.

Fixed in DP9. Capturing here in case anyone runs into it.