06762: chelnov: Sound music slowdown when big sprites are on screen and the player has a weapon with multiple shot

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06762	Sound	Minor	Always	Nov 16, 2017, 08:39	Feb 7, 2020, 09:46

Tester	Augusto	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows 10 (64-bit)
Status [?]	Acknowledged			Driver	dataeast/karnov.cpp
Version	0.191	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	06762: chelnov: Sound music slowdown when big sprites are on screen and the player has a weapon with multiple shot
Description	If big sprites is on screen and the player has a weapon with multiple shot at once the music is slowdown. Hit multiple shoots in a boss and the music will slowdown. MAME previous versions before 12-2016 not slowdown the music when bosses are hits with multiples shoots. The same issue is in current MAME version with Midnight Resistance (several sprites or few big sprites on screen) and Secret Agent (some areas) both slowdown the music being both games from Data East.
Steps To Reproduce
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	chelnov

Attached Files

No.14443 Kale Developer Nov 18, 2017, 23:18	It has been reported multiple times that Midnight Resistance is plagued with slowdowns on real HW as well, so please stop moaning about it.
No.17375 MetalGod Senior Tester Jan 25, 2020, 14:27 edited on: Jan 28, 2020, 15:39	This is the original hardware. The only slowdowns I've seen are in 17:10 and 26:38. It doesn't seem to affect the music
No.17379 MetalliC Developer Feb 1, 2020, 15:47	not sure if this issue still actual. I've did playthrough but haven't noticed music slowdowns, only gameplay slowdowns in few places like 17:10 and 26:38 in above video.
No.17389 TServo2049 Tester Feb 4, 2020, 18:58 edited on: Feb 4, 2020, 19:11	I wonder, if this is still happening, could it be the same kind of problem as the dec0 driver, as logged in MT #6740? The hardware may be different, but it’s the same developer, so maybe they used similar weird instruction tricks here that MAME is also not emulating.
No.17392 Augusto Tester Feb 7, 2020, 06:29	I has tested in 0.217 and the slowdown is less than in 0.191. Stage 5 Boss and player using the fire weapon in maximum power and speed has slowdown in music and gameplay mainly when the boss attack using 3 little birds, but now is less slowdown than 0.191 and the slowdown is more in music than gameplay. The slowdown in music is when has big sprites and using an weapong with multiple shoots pressing fire button very fast.
No.17394 JSDS Tester Feb 7, 2020, 09:46 edited on: Feb 10, 2020, 15:29	Another video. I hear music slowdown around 8:55 and 12:31. It may happen when you use "iron-whip" weapon with "fast" shoot.