When using Live Time mode for long exposures, I noticed it stops updating the display after about 18 seconds. It should keep updating it until the exposure is stopped. The actual final exposure is OK. And is different from what is shown during shooting. E.G. Firing a flash in the scene after it stops updating does not affect the displayed image. But the flash is evident in the final picture. Has anyone else experienced this? Is there a fix? Have I got some wrong setting.