i have the exact same issue. It started this week, haven’t had issues before that and i have been playing since launch.
*tried -repair
*deleted gw2.dat re-patched
*uninstalled overwolf
i5-4670K 3,4GHz
Asus Radeon R9 280X DC II TOP OC 3GB GDDR5
8gb – DDR3 1600 MHz
ASUS Z87 motherboard
win 8.1 64bit