Dolphin, the GameCube and Wii emulator - Forums

My Wii U is connected to my AV receiver via HDMI.
My AV receiver supports Dolby Pro Logic II (DPLII).
Both my Wii U and its Wii emulator are set to output surround audio.
When I play any DPLII supported game my AV receiver correctly displays PLII Game and outputs surround audio through my 5.1 speakers.

My PC is also connected via Nvidia RTX 3070 HDMI to the AV receiver.

I've found that to get surround sound output from Dolphin 5.0 I have to select DSP LLE not HLE as HLE seems to strip the rear channels from the stereo output sent to my AV receiver. Tested with GameCube Super Mario Sunshine sound options the rear channels are only present when decoding LLE output with DPLII on my AV receiver. The problem is that using LLE over HDMI Wii Sports Resort when I get to the canoeing lake stutters very badly. Setting audio back to HLE and the stuttering goes away and the game runs very smoothly at 4K. CPU and GPU % are very low. I've tested with every combination of DSP emulation engines and backends.

Then I thought I'd test using Realtek analog audio headphone output on my MSI B460M Mortar WIFI motherboard into RCA L/R sockets on my AV receiver. That fixed it! Now I can use LLE surround audio and there is no stuttering in Wii Sports Resort. Not ideal though as it's another cable and analog can be a bit noisy as it can pick up computer noise especially noticeable in quieter moments.

Is there a known issue with Nvidia HDMI audio and DSP LLE?

The DPL II decoder in Dolphin has little to no testing, AFAICT, so this might be an unknown issue. It should work with DSP LLE, though...

(07-18-2021, 08:33 AM)mbc07 Wrote: [ -> ]The DPL II decoder in Dolphin has little to no testing, AFAICT, so this might be an unknown issue. It should work with DSP LLE, though...

I just remembered that my i5 10400 has built-in graphics and can do digital audio output via the motherboard HDMI socket. Connected to my AV receiver and set Dolphin sound emulation to DSP LLE. No issues with game/sound stuttering and surround sound working. So it seems it's just an issue with Nvidia High Definition Audio HDMI output on my RTX 3070 and Dolphin Emulator. I don't have any issues with Nvidia HDA when using other games or apps.

(07-19-2021, 04:48 AM)Anythingyoulike Wrote: [ -> ]I just remembered that my i5 10400 has built-in graphics and can do digital audio output via the motherboard HDMI socket. Connected to my AV receiver and set Dolphin sound emulation to DSP LLE. No issues with game/sound stuttering and surround sound working. So it seems it's just an issue with Nvidia High Definition Audio HDMI output on my RTX 3070 and Dolphin Emulator. I don't have any issues with Nvidia HDA when using other games or apps.

I'm no longer having issues with Nvidia HDMI HDA and DSP LLE Recompiler running version 5.0.14738 of Dolphin.

Now the only issue is some games do not run smoothly with LLE but they do with HLE.

Wii Sports and Sports Resort: LLE or HLE smooth 60 fps possible
Indiana Jones and the Staff of Kings: HLE nearly always 60 fps, LLE occasionally slows down (Game crash issues fixed in recent point release)
Star Wars Rogue Squadron II: HLE nearly always 60 fps, LLE occasionally slows down (Game crash issues fixed in recent point release)

Interesting that Indiana Jones and Rogue Squadron both used to have crash issues that were fixed and both exhibit LLE slowdowns. Hopefully if this is replicated by others it can be fixed.