Emulator

Game Name?
Any Wii game using a Wiimote on multiple clients including
New Super Mario Bros. Wii (NTSC) Rev. 2
Mario Kart Wii (NTSC)

Game ID?
SMNE01
RMCE01

What's the problem? Describe what went wrong in few words.

When host and client are each assigned an Emulated Wiimote with no attachment, a desync pop-up occurs and is also written in the chat log as soon as the game is started. If no Wiimotes are assigned, or if a Wiimote is only assigned to a single client, the game correctly syncs.

This issue is likely identical to https://code.google.com/p/dolphin-emu/issues/detail?id=8094

What did you expect to happen instead?

Game to correctly sync with multiple Wiimotes.

What steps will reproduce the problem?

1. On each machine (or on same machine), setup fresh portable Dolphin directory using latest development build.
2. Set path to ISO directory
3. Setup an Emulated Wiimote in slots 1 and 2 with each Extension set to "None"
4. Host a netplay session and assign one client Wiimote 1 and the other client Wiimote 2.
5. After hitting Start, desync popup appears. Changing audio settings sometimes causes popup to not display, but desync will be noted in the chat log.

This is been replicated with two copies running on the same machine, across two computers on a local network, and with another computer on a remote network. In all cases, settings are identical. Replicating or deleting Cache and Wii (shouldn't be necessary due to dummy NAND being used) folder have made no difference. Disabling dual core has not resulted in a successful sync either.

Dolphin 3.5 and 3.5-367 are old versions of Dolphin that have
known issues and bugs, so don't report issues about them and test the
latest Dolphin version first.
Which versions of Dolphin did you test on?

4.0-6970
4.0-6928
4.0-6554

Does using an older version of Dolphin solve your issue? If yes, which
versions of Dolphin used to work?

No

What are your PC specifications? (including, but not limited to: Operating
System, CPU and GPU)

Computer 1:
OS: Windows 8.1 x64
CPU: Intel Core i7 5820k
GPU: NVIDIA GTX 980

Computer 2:
OS: Windows 8.1 x64
CPU: Intel Core i7 3630QM
GPU: AMD Radeon HD 7800M

Is there any other relevant information? (e.g. logs, screenshots,
configuration files)

Log file: http://pastie.org/private/7vagdbqayxslwpuvxpdoma