Game crashing consistently at 25-30 minutes of in-game time since June 18 patch

Game Version/Build: 101.103.48086.0 (#179158) 23798925

The Problem:
Since the June 18 patch, the game crashes consistently at approximately 25-30 minutes of in-game time during both replays and live gameplay. Frame drops/stutters are sometimes visible immediately before the crash. Crashes occasionally take the entire OS down (confirmed full system crashes in Windows Reliability Monitor on 6/29). Issue started around June 21-22 with no hardware or software changes on my end. No issues for over a year prior on the same setup.

Reproduction Steps:

  1. Launch AoE2 DE via Steam
  2. Watch any replay or play a live game vs AI
  3. Game crashes consistently between 25-30 minutes of in-game time
  4. Frame drops/stutters visible in the seconds before crash
  5. Occasionally takes entire Windows OS down with it

Crash Signature:

  • Fault Module: StackHash_71cd
  • Exception Code: c0000005 (access violation)
  • No entries appear in Windows Event Viewer Application or System logs after crashes
  • Confirmed via Windows Reliability Monitor

System:

  • GPU: GTX 1080 (8GB VRAM), driver 582.53
  • Windows 11 25H2
  • Steam version

What I tried (all unsuccessful):

  • RAM test — clean
  • Full clean DDU driver reinstall, tested multiple driver versions (582.66 and 582.53)
  • Full clean AoE2 reinstall including manual folder deletion
  • Windows sfc /scannow (found and repaired corrupted files) + DISM /RestoreHealth
  • Running with and without CaptureAge
  • Running as administrator on/off
  • -d3d11only launch parameter — stabilized FPS at 60 throughout (vs dropping to 10-12 previously) and pushed crash slightly later (28-30 min vs 25-27 min) but did not prevent it

Notes:
The -d3d11only flag improving FPS stability but not preventing the crash suggests a memory management issue in the game simulation layer introduced in the June 18 patch, unrelated to rendering or system load. CPU stays at ~30% and GPU at 25-55% at crash time — no resource ceiling is being hit.

Hi, anyone who sees this, any advice on something else I could try to fix it? I make yt vids weekly and this issue makes it impossible to make them.