paranoidparrot

Seems to have been the ambient sounds, as suggested. Slider set to zero, no issues. Hopefully it'll stay that way. Still don't get why it'd only occur where it did but I'm not going to question it. Thanks.

I'll read the other link later, thanks for that also. 

OK I'll have a look at that when I get chance. Right now I've done a BG Trilogy based install since I already had a boatload of mods archived from way back when, installing each mod one by one, one component at a time like a neanderthal. I'll post a list of which ones I've got installed in a bit. For now I've backed up my game directories at various points throughout the install process so it's easy for me to revert back to an earlier stage. I'm trying to narrow down exactly which mod is causing the problem.

As for the problem itself, basically something in Beregost/Nashkel slows everything down to a crawl making the game unplayable. Things keep processing but nothing visually updates. But just those two places. I've used CLUAConsole:MoveToArea("ARxxxx") to skip around all over the place, wilderness areas, Gullykin, Baldur's Gate itself, Athkatla, and the problem doesn't present there. I've even teleported into the middle of the Xvart village and had several dozen hostiles active at once and it's fine there. Just Beregost/Nashkel from what I can tell so far. 

Installed mods as follows, working from an install order list I made ages ago (this all worked perfectly on my old machine way back in the day, 10 years ago or so, I just never got around to playing beyond the Nashkel mines back then, but had no problems like this back then). To my knowledge they're all up to date as of about two weeks ago. I honestly can't recall what some of this stuff's supposed to do so there might be some daft combinations here.

I'm using the original release game CDs, fully patched to TOTSC v5512/SOA v26498. 

I've installed a few old non-weidu mods from back then, files copied to the BG2 override folder - 

* a level 50 ruleset which I think was EXP tables, progression, etc. Probably overridden by later mods.

* Juggernaut golem fix - I think they used to get stuck in doorways and this lets them pass through?

* A magic missile arrow mod  

Weidu mods as follows

* PrRings - don't know what this does, no readme available

* Oversight V13 - everything except Cleric kits

* D0Tweak V20

* D0Questpack V32

* BG2 Fixpack V10

* BG Trilogy V118

* cdtweaks V3 (the one that replaces the old BG1/2 tweak/ease of use packs

* BG1 Unfinished business V12

* Dark Side of the Sword Coast V217

* Northern Tales V170a

* Patch the above to 171

* BG1NPC V23

* BG1NPC Music V6

* Bone Hill 275a

* Thalantyr Item Upgrade V3.7

* Drizzt saga (not sure of version tbh)

* G3 anniversary mod V9

* Horn of valhalla mod V2

* P&P Celestials V5

* Demon Summoning Ritual V6

* Planar Sphere Mod 26c

* AbyStore V3

* Wildmage V16

* BGQE V7 (Mini quests and encounters)

* BG2 Unfinished Business V19

* aTweaks V451

* BG2 Banter pack V12

* NPC Flirt V102

*1pp V2 (paperdoll/artwork changes?)

* Assassinations V8

* Snakes on a plane V3.3

*Turnip golem V4

*Lucy the wyvern V4a

* Adalon's Blood V10

* Jerry ZingerV4

* Tower Of Deception V3.2

* Ascension V1.424

* Wiemer Item Upgrade V38

* Stuff Of The Magi V4

* Turnabout V1

* Redemption V1.2

* Alternatives V12

* Arena V1

* Elistaree's Song V3.1

* Tales of the Deep Gardens V12.2

* Innershade V9.2

* White Queen V6.2

* Yvette V4

* Foundling V3.2

* I shall never forget V5.2

* Fishing For Trouble

* Slandor

* Every Mod and Dog V6

* Cliffkey/Mod FOr The Orderly V4

* M7 Tweaks

* Trap Revisions V1

* TobEX - should this come sooner? IDK

* Turambar Fixes/Tweaks

* Knock spell V1.1

* Picky Familiars V1.1

* High Level Abilities - the one that makes mage/cleric HLAs innates instead of spells

* Sword of Noober V1.1

* Wheels of Prophecy V6

* Unique containers V3

* Infinity Animations - everything as far as I know

* Vecna V23

* SCS V30

* Imoen/Mazzy/Sarevok/Viconia/Yoshimo friendship mods

* Widescreen mod (1920*1080)

And I think that's it...

I'm running it on a Win10 Home 64bit laptop, i7-4710MQ 2.5GHz, 8Gb Ram, nvidia GeForce GTX 860M. Everything in BG Config set to the best performance possible. Hardware isn't the issue.

Something in those mods is screwing with Beregost and Nashkel. Any ideas what it might be?

I have not specifically looked, no. It was pushing 4am when I posted. Didn't have time to scour the forums looking. I'll get right on it. Thanks.