Rhythm Heaven Fever, Shrimp Shuffle slowdown

[FernandoLemon]

I'm experiencing a major problem when playing Rhythm Heaven Fever (NA version, specifically), as the Shrimp Shuffle minigame causes the emulator's framerate to drop from 60 FPS to 30 FPS, rendering the game unplayable. This is a known issue, however, it had supposedly been fixed. I'm currently using Dolphin 5.0-12247 x64, default settings.

The Dolphin Wiki article on the game makes note of it, presenting two solutions:

• Fixed by enabling "External Frame Buffer (XFB)" (outdated, as newer versions have switched to Hybrid XFB, which means the settings are different)
• Fixed with Hybrid XFB in 5.0-5874 (should work by default, but doesn't - might be an error with specific settings?)
  

I played around with the XFB settings a bit, but nothing came of it - disabling "Store XFB Copies to Texture Only" causes the entire game to slow down, while any combination of "Immediately Present XFB" and "Skip Presenting Duplicate Frames" has no apparent effect: the framerate still drops when playing Shrimp Shuffle.

Of note is that the article also mentions that the Micro-Row minigame also has issues that can be solved with XFB; however, it works perfectly with the default settings.


My current settings:

Code:

[Enhancements]
ArbitraryMipmapDetection = True
DisableCopyFilter = True
ForceTrueColor = True
[Hacks]
BBoxEnable = False
DeferEFBCopies = True
EFBEmulateFormatChanges = False
EFBScaledCopy = True
EFBToTextureEnable = True
SkipDuplicateXFBs = True
XFBToTextureEnable = True
ImmediateXFBEnable = False
[Settings]
BackendMultithreading = True
FastDepthCalc = True
InternalResolution = 1
SaveTextureCacheToState = True

And my specs, just in case:

• Operating System: Windows 7 x64
• Processor: Intel Core i3-3240 CPU 3.40 GHz
• Video Card: ATI Radeon HD 5450
• RAM: 4,00 GB
  

Okay, I believe that should be all the pertinent information. The question now is, any suggestions on how to fix this problem?