I am recording SDI coming from telecine. On several occasions I have had missing frames, about 24-30 frames long in the middle of a sequence; no warning given by Decklink.
I recorded SD PAL to Quicktime ProresHQ 422. The RAID0 disks (2ea Constellation 2TB) were recently changed but make no difference.
The clip should be continuous, usually about 20-30 minutes. Since there is burned-in timecode, I check if the timecode holds from beginning to end. If there is a drop I have to start a new recording; capturing without device control using Media Express latest version.