ID 427913 - Looping a sequence with a monitor out device skips frames on the monitor out display and the Timeline Viewer

Problem summary
Looping a sequence with a monitor out device skips frames on the monitor out display and the Timeline Viewer

Customer reported version
nuke.12.0v4

Customer reported platform
centos7

Steps to reproduce

1) Open Nuke Studio 

2) Import the attached footage and add it to a sequence

3) In Window>Monitor Output, select a Monitor Out device, such as an AJA or Blackmagic card

4) Play the sequence on loop, you can see not all the frames at the beginning/end don't play correctly

Expected behaviour
For Nuke Studio to play all the frames when looping

Actual behaviour

On the monitor out display, the last few frames are skipped at the end of the loop

On the Viewer, the some of the first frames are skipped
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Workaround
Unknown.

Reproduced by support
This bug has been reproduced in:

Nuke 12.1v1 - Windows 10 - CentOS 7.7 - MacOSX 10.13

Nuke 12.0v1 - Windows 10 - CentOS 7.7 - regression

Unable to reproduce bug in:
Nuke 11.3v6 - Windows 10 - CentOS 7.7 - MacOSX 10.13

Earliest version tested
Nuke 11.3v6 - This issue doesn't appear in this version and has regressed