Meta Avatars -- tons of asserts and errors

I'm having extreme difficulty networking Meta Avatars with Photon Fusion. I'm using SampleAvatarEntity and trying to set the configuration when the object is spawned, and then I try to load the avatar with the appropriate User ID. Loading the avatars seems to work. But I get all kinds of asserts and errors when calling methods, even innocuous ones like SetLocal().

For example:

[code]

_metaAvatar.SetBodyTracking(bodyTrackingBehavior: _avatarBodyTrackingBehavior);
_metaAvatar.SetIsLocal(true);

[/code]

The second line there leads to:

[ovrAvatar2 entity] Assertion failed: ovrAvatar2Streaming_PlaybackStop failed with NotFound

Even if I wait for CurrentState > Created.

Applying stream data received over the network completely fails. 

I'm aware of the loopback scene but it's somewhat irrelevant because in that case, the avatars are set up ahead of time and not dynamically instantiated. 

Does anyone have some tips on how to figure this API out? I've looked at the code but it's a bit of a mess and extremely stateful. Hard to say where the problem could be.