05314: outrun shangon: Occasional sound glitches - "skipping" in music

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
05314	Sound	Minor	Sometimes	Sep 27, 2013, 23:46	Sep 29, 2013, 01:41

Tester	jonuk76	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	No change required	OS	Windows Vista/7/8 (64-bit)
Status [?]	Closed			Driver	sega/segaorun.cpp
Version	0.150	Fixed in Version		Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	05314: outrun shangon: Occasional sound glitches - "skipping" in music
Description	Infrequent skipping of music during game play (perhaps every few minutes, it varies). I did not notice it happening in 0.149 therefore I think it could be a possible bug.
Steps To Reproduce	Playing one of the affected games for a few minutes should be enough to observe this happening.
Additional Information	Tested on MAME normal binary and MAMEUI64 and had the same issue in both. I don't get the problem in MAMEUI 0.149. I also tried toutrun which uses the same driver, but did not notice the problem in this game.
Github Commit

Flags
Regression Version
Affected Sets / Systems	outrun shangon

Attached Files

No.09851 Fujix Administrator Sep 28, 2013, 05:15	No repro here with 0.150. Resetting the config ini to default may help solving the issue for you. If not, please upload your mame.ini file here for investigation.
No.09854 jonuk76 Tester Sep 28, 2013, 13:42	Hi. Thanks for checking this out. After a little experimentation I've found that disabling Triple Buffering in mame.ini seems to have solved this issue. I've enabled this at some point to stop screen tearing in some games. When exiting the games with triple buffering enabled the average speed was reported by MAME as something less than 100% (e.g. 99.92%). With triple buffering disabled, this goes to 100%. Having re-run Outrun on MAMEUI 0.149 with this option enabled, it also gets the occasional sound skipping. I therefore presume it's not an issue specific to 0.150. Apologies for any confusion.
No.09855 Fujix Administrator Sep 28, 2013, 15:59	Yes, it is known that some speed options which forcibly sync with another timing such like LCD update rather than the original in-game update frequency, will cause nonconstant sound playback.