I was about to post something similar. My son and I were playing ddragon today on lr-mame2003 Pi3 4. Going from really sluggish to suddenly really fast, so I'd also like to know. I also got to the last boss in Metal Slug 3 and it was also really sluggish, but choppy audio too. . I do have Floobs overlay pack running, which I need to test disabled emulation emulates the original systems, so if it slows-down, so will the emulated version. .
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