Pherim corrected this by converting the meshes in each nif to TriShapes, which resolved the problem.

This mesh was identified by Pherim as containing TriStrips with composed of multiple strip lengths, this was causing the Oblivion game engine to make multiple draw calls for each strip segment rather one for each TriStrip which was impacting performance. If you find any bugs with the fixes or any bugs with the official mods themselves please report them to either of us. It is recommended to not activate the Thieves Den' SSSB (Sigil Stone Sound Bug) fix plug-in 'DLCThievesDen - Unofficial Patch - SSSB.esp' on an existing game, but rather only on a new game, as otherwise the middle deck of the Black Flag could lose its doors (as their position is stored in the save file) and/or any objects already dropped in this cell could be lost. Use dev_akm's compatibility patch instead. ESP's after the UODP ones with OBMM or equivalent.) If you use the Horse Armor Pack patch with Slof's Armored Horses, the Slof's horses' reins may disappear. If you use the UODP overtop of Unnerfed, Oblivion may crash on launch. The UODP is currently not compatible with the JOG's Official Plugins Unnerfed mod because it modifies the original Bethesda plug-in ESP files. (The self-installing version will set the appropriate dates use OBMM or equivalent if you use the manual version to adjust the load order.) Merging, editing or otherwise modifying them using the Elder Scrolls Construction Set or other utilities may cause them to stop functioning or cause severe bugs in your game! These plugins MUST load after the DLC's that they patch reversing this load order, or activating the UODP ESP's without the official DLC's that they patch present, can cause Oblivion to crash on launch or load of a save. Because of this, these are not standard plug-in ESP files.

NOTE: These fixed plugins use the ESP master (aka mod de-isolation) method which means you still need the original plugins for these plugins to work! The plug-ins are not a redistribution of modified original Bethesda plug-ins, but contain only changes and have the original plug-ins set as masters. The aim of this mod is to fix the bugs existing in the official mods released by Bethesda. By Quarn, Kivan, Arthmoor, PrinceShroob, and Sigurð Stormhand

Unofficial oblivion dlcs