Impossible glitch-free sound on OS X?

[wilshy]

This hasn't been reported yet on here, however I'm getting small stutter on games which are accompanied with sound clicking / glitching.

Seems to be whatever game, so it feels more like it's the emulation core at fault.

I've tried with the stable version and the latest development version both with the same issue.

This is running on a Macbook Air 13".

[Christian]

Hi Frode, thanks for such a great emulator.

I'm having an issue on my Macbook Air. I get a fairly frequent glitch/pop/crack in the sound no matter what settings I use. I've even stripped the configuration right back to the simplest/fastest settings but the problem persists. Some games seem worse than others. A good example of a bad one is the tune in Elite.

I've tried both stable and developer versions. The Air is a 2013 model with an i5 Haswell CPU. It's running Yosemite. The graphics appear to be dead smooth (50Hz) with no slowdown and when running a minimal configuration, Activity Monitor reports about 25-30% cpu usage for FS-UAE, rising to about 75-80% with everything turned on.

I've pretty much tried all settings including increasing the sound buffer to 99! I can make the issue worse but not better if you know what I mean. It gets better up to a point and then nothing seems to help.

I also quickly tried running things on my desktop hackintosh and had a similar problem although I need to test further on that machine. It's an i7 2600k also running Yosemite.

I realise I should post the log file and will do so later today.

Thanks again

[wilshy]

Have much the same issue on my MBA i5 running Yosemite. I suspect it's Yosemite as FS was absolutely fine before that, however a mates MacMini on Yosemite is absolutely fine.

I did everything you have said as well.

Hopefully a fix will happen as I'm now running WinUAE under Parallels which doesn't have the issue at all.

[FrodeSolheim]

Originally Posted by Christian

I've pretty much tried all settings including increasing the sound buffer to 99! I can make the issue worse but not better if you know what I mean. It gets better up to a point and then nothing seems to help.

I also quickly tried running things on my desktop hackintosh and had a similar problem although I need to test further on that machine. It's an i7 2600k also running Yosemite.

I haven't noticed anything similar on 10.10 (I've got an older non-Air Macbook Pro here).

But "increasing the sound buffer to 99"... what setting are you tuning? This isn't an FS-UAE setting (FS-UAE does have it's own sound buffer setting which can be tweaked though).

Originally Posted by Christian

I realise I should post the log file and will do so later today.

Yes, please do Also, it would help if you could enable the performance graphics (Ctrl+F10) and take a screenshot of the FS-UAE window while you experience sound stuttering.

@wilshy you can do the same (screenshot(s) and log file from the same session, please)

[Christian]

Hi Frode, sorry about the delay on this.

I've attached a couple of screenshots and the log. Config is set as basic as possible on the developer version. I've attached two screenshots as there doesn't always seem to be a correlation between the sound graph rising and the sound breaking up. The sound was breaking up in both cases.

Hope this helps

Edit: Yes I was referring to the fs-uae audio buffer target size setting in the launcher, which defaults to 40ms.

[wilshy]

Hi Frode, sorry for the delay here's mine. I can see there's a mismatch in the refresh rates between system and emulation, and that judders about as the sound judders / glitches.

Hopefully this will be of some help for me.

[FrodeSolheim]

@wilshy The emu graph should be (more or less) flat with 50.0 fps. For some reason, only 48 frames per second is emulated, and this is very likely the cause of the sound judder. The audio buffers are regularly emptied because not enough sound data is generated. So the sound issue is just a symptom, and not a problem!

It does sound unlikely that your computer(s) should not be able to emulate 50 frames per second, so perhaps a timing issue or something else ... ? (but I also find it a bit strange that you also have the same problem on another even more powerful computer...)

Can you try with the development version of FS-UAE (currently 2.5.32dev)?

[wilshy]

Hi Frode, thanks for the response. Early very brief tests are positive. Running at an almost stable 50fps on the dev version

I will do some further tests once I return from a work trip. But it was doing it all the time so I'm pretty sure this will have sorted it.

Great stuff!

[amiga_Forever]

Been ok here on Macbook Pro Retina 13' running 10.10, and dev build of FS-UAE.