lr-genesisplus-gx audio problem on Retropie 4.7.1

[mitu]

Try removing your shader preset for the core and see if you still get the same slowdown.

[REK607]

It worked! So were there many shaders then? I still preserve the content directoru ones and it's working smooth and fine.

[dankcushions]

@rek607 we can't see what shader you have active but from the pragmas it looks like lcd_zfast. lr-genesis-plus-gx is particularly bandwidth expensive so it's unlikely to work well with any shader. if you change your genesis/megadrive emulator to lr-picodrive it should be able to handle a shader.

[BuZz]

Can lower your output resolution also - I run at 720p on my 1080p screen and use a scanline shader. I actually think it looks better actually, with the scanlines applied at that resolution and then upscaled. This obviously depends on your screen, but it may be a good compromise.

[BuZz]

I also wrote this before checking your log. Looks like you may already be running at a lower res - should have checked that first. Having said that I'm sure I've been running this emulator with zfast scanline shader myself without issue but will check (on RPI 3).

[REK607]

@buzz thing is on Retropie 4.6 I had not a single issue with shaders or even sound quality, while on 4.7.1 I had to lower these specs in order to make it run and sound smoothly. I'm now testing this on Mega CD and I had to remove shaders, bilinear filtering and put sound quality to normal (then exit the game and run it again), that solves the problem. Is there something else that can be done maybe? As I say on 4.6 I had no issue with my favourite audio and video presets.

[mitu]

I don't think it's a RetroPie version issue - more likely an emulator update between 4.6 and now that changed the performance of lr-genesis-plus-gx. Do you have the same slowdown with lr-picodrive ?

[REK607]

@mitu that makes sense indeed. lr-picrodrive runs flawlessly as always and is my B plan if I can't solve the issue.

[dankcushions]

@rek607 note that picodrive was the default genesis/megadrive emulator until February this year, so genesis-plus-gx was default in 4.6, but if you updated to 4.6 from an earlier version, you may have been using lr-picodrive.

[REK607]

@dankcushions yes! I did the change when I found this new emulator was ported to libretro. At the end I found that the main problem in my lr-genesis-plus-gx performance is the bilinear filter. If I turn it off it's working 58-60 fps with very good sound quality. So as I see it maybe I overloaded my raspberry pi 3B too much, if I'm correct is definitely something to have in mind if you dont have a rpi3B+ or rpi4. SegaCD is working fine too now!