Game locks up while alt-tabbing in Kugane or housing districts.

Time: Most recently, approx. 4:15PM PST 6/22/2017
Frequency: Very frequent.
World name: Balmung.
Character name: Kokomoco Komoco
Class/Level: 67 BLM
Party or solo: Both
Area and coordinates: Kugane
Housing: All wards

Steps:
1. Run game using borderless windowed mode on DX11 client
2. Enter either Kagune or the housing districts (Lavender Beds, Goblet, Mists)
3. Alt-tab.
4. Game will very probably lock-up, resulting in a "Program is not responding" error. Will sometimes recover, but usually results in a server disconnect or a hard restart of the client being required.

Addendum: Error only occurs in Kagune and housing districts. Other cities and zones are unaffected. Interior of houses and apartments are also unaffected. Only the exterior zones produce the error. Kagune produces the error at a much higher rate than the housing districts.
Error also occurred prior to the release of stormblood, but was then limited only to housing districts.

Connection Specs
- Type of internet connection/provider: Broadband, Shaw Cable.

Driver status: Recently updated.

■ PC Specs
CPU: AMD FX-8320 @ 3.5GHZ
GPU: AMD R9 290X 4GB
RAM: 16GB
HDD: 2x2TB
Sound Card: Asus Xonar DGX
Monitors: 1x 1920x1080 (Secondary), 1x 3840x2160 (Primary).