Sure have, but none related to the firearms themselves, and nothing that required repair.
Sig 522 - 1000 round torture test with dirty bulk ammo...somewhere around the 800 round mark it started having FTE's.
Ruger Single Six - again, dirty bulk ammo and a long day at the range resulted in the cylinder locking up from all the crud.
S&W 40fs and 40c - Light loads and split cases using Tula resulted in many FTE's and occasionally jammed the slides.
Cleaned the Sig and Ruger at the range, and they functioned like I expect them to when properly cleaned/lubed.
Still using Tula in the M&P's. On purpose. Still have FTE's, etc. Gives me lots of practice clearing malfs...