Emulator

The AR might be looking for its memcard. Does making an image of the AR memcard and loading the image in Dolphin fix this hang?

I have no memory card with it; I bought it disc only a few months ago.

The Action Replay will look for the memory card in second slot, and it doesn't have to be its own memcard. The Mad Catz branded one will work as well. Not sure about the Nintendo branded one.

Still an issue as of 5.0-16526. Note that this only applies to the Wii-compatible Action Replay disc; older versions (at least Action Replay Max version 1.14A) work correctly. There must be no device in either memory card slot for the Wii-compatible version to boot. It remains frozen even if the device is removed after booting. This is probably a bug with Dolphin, but I haven't confirmed on real hardware. The Wii-compatible action replay doesn't need a memory card to store discs, but it does support loading stuff off of an SD card adapter in the memory card slots (which isn't supported, see #11757), so maybe something is tripping this up?

Action Replay Max will freeze if a device that is not a memory card (e.g. the microphone or AGP) is inserted into slot B, but it'll show a message explaining that the action replay hardware needs to be inserted. Once the device is inserted things behave properly. If no device is inserted, the message will appear but the background screen will continue to animate. This is probably correct behavior on Dolphin's side, but I haven't confirmed it on real hardware either. (This also only works correctly with raw memcards; using GCI folders will result in Dolphin closing due to #11324.)