One more setting that seems to give some extra speed is Enable Block Merging in the game properties (right-click on the game in Dolphin's game browser). Gaining speed in exchange for some visual quality is also achieved by setting EFB scale to x2 or x1.

if you're struggling for speed, you can try disabling Fog, Native Mips, Pixel Lighting and CPU->EFB Access, as these don't seem to be needed for the game.

VSync can also help against scroll jerkiness. for better image quality you can also check 'Force Bi-/Trilinear Filtering' (especially for 2D stuff), 'EFB scaled Copy', 16x Anisotropic Filtering and, if you have a strong machine, SSAA 4x or 9x. Pretty much everything at default is fine for this game, but have EFB Copy to Texture and Safe Texture Cache set to Fast! Lock threads to core: Enabled (disabled can be faster, however, it can make the game freeze when loading the world map) CPU Emulator Engine: JIT Recompiler or JITIL experimental Recompiler (try what works best for you it seems that on 32bit, JITIL is faster while on 64bit JIT is faster) Donkey Kong Country Returns (tested version: NTSC-U)

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