I'm also experiencing more choppy-than normal gameplay. It also occured in the vanilla game (probably since my specs aren't too hot), but at a much later time when many many ships were onscreen. Now it occcurs much earlier in the game, sometimes when only one ship is visible. Sometimes I experience none at all. It seems mostly random. Here are my specs and debug; (EDIT: I really think I posted too much. Sorry, first time with the debug and all... feel free to prune it mods

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Pentium 4, 2.0 GHz
512 RAM
All in wonder 9000, 64 mb
Debug Message: Version v1.6 beta 1 Dark Avatar last updated on: Tue Apr 3 16:54:35 2007
Debug Message: Checking DX Version.
Debug Message: *********DXDiag info follows.*********
System Info
Time: 5/28/2007, 19:15:51
DirectX Version: DirectX 9.0c (4.09.0000.0904)
Machine Name: RHINEVILLE
Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 2 (2600.xpsp_sp2_gdr.050301-1519)
Languages: English (Regional Setting: English)
System Manufacturer: IBM
System Model: 8311KHU
BIOS: PhoenixBIOS 4.0 Release 6.0 for IBM NetVista.
Processor: Intel(R) Pentium(R) 4 CPU 2.00GHz
Physical Memory: 510MB RAM
Page File: 269MB used, 1980MB available
Windows Dir: C:\WINDOWS
Display Info
Display device 1:
Device Name: \\.\DISPLAY1
Card Name: ALL-IN-WONDER 9000
Manufacturer: ATI Technologies Inc.
Chip Type: RADEON 9000 PRO AGP (0x4966)
DAC Type: Internal DAC(400MHz)
Key Device: Enum\PCI\VEN_1002&DEV_4966&SUBSYS_4F721002&REV_01
Display Memory: 64.0 MB
Current Display Mode: 1280 x 960 (32 bit) (60Hz)
Monitor Name: Plug and Play Monitor
Monitor Max Resolution: 1600,1200
Driver Name: ati2dvag.dll
Driver Version: 6.14.0010.6505
Driver Date: 11/30/2004 23:13:41
DirectX Acceleration Enabled: Yes
Sound info
Sound device 1:
Description: SoundMAX Digital Audio
Default Sound Playback: Yes
Default Voice Playback: Yes
Hardware ID: PCI\VEN_8086&DEV_24C5&SUBSYS_02671014&REV_01
Manufacturer ID: 1
Product ID: 100
Driver Name: smwdm.sys
Provider: Analog Devices
Driver Version: 5.12.0001.3511
Driver Date: 6/17/2002 16:43:14
Type: WDM
Other Drivers:
Acceleration Level: 3
Cap Flags: 0
Min/Max Sample Rate: 0, 0
Debug Message: *********END dxdiag info.*********
Debug Message: Entering WinMain
Debug Message: ******* Starting Game Shell *******
Debug Message: Going Fullscreen
Debug Message: Preparing to change display settings.
Debug Message: Using multilsample setting: D3DMULTISAMPLE_NONE
Debug Message: Game Resolution: 1024 x 768
Debug Message: Running fullscreen.
Debug Message: HAL (sw vp): ALL-IN-WONDER 9000
Debug Message: D3DPRESENT_INTERVAL_DEFAULT
Debug Message: Refresh rate: 60
Debug Message: Bit Depth: 32 bit.
.....