I believe it is the dynamic line manager that is actually the problem. I have to output about a 100 promos a session. Seems like a great reason to use the "Render que". After getting about 15 spots into the Render que, Premire starts to hang up (like I can't "goto inpoint") and Encoder will stop adding to the que. At this point I have to reboot and resend everything back into the que. Most days I just render the spots one at a time. This has become a huge waste of time.
MacPro (trash Can), High Sierra
64gb, 2 D700,
Adobe 2018 apps

Since the springupdate 12.1 - april, mediaencoder on OSX 10.13.4 became totally useless / unpredictable.
First is that encoding to HEVC is now missing the "max bitrate" setting. Only "target bitrate" is available.
Whatever I select, ME creates extreme huge temp. M4V files .
For example: HEVC traget 13Mbit/s estimatetd 3000MByte VBR = creates files of 25 GB..then tries to multiplex to a MP4 file, and therefor consumes every available discspace (up to 55GB in my case)...the OSX raises a warning ...running out of diskspace....the now created MP4 has now 11GB and is only playing halfway.

If set to CBR , hardware accelaration is not selectable....your system does not support hardware accelerated.... (we are talking about a brandnew IMACPRO with ATI-Graphics !!!)

Set to VBR ...(see above).

ME is randomly crashing and telling me various TC's where the estimated error should be ....

tried this with various timelines and material ...always the same ...
...reverting back to V 12.01 ...everything is fine .

IMAC Pro 8core ATI Graphics 32GB RAM
OSX 10.13.4

When exporting to h.264 from Premiere Pro CC 2018, the Media Encoder ignores the first set of keyframes in audio effects. This results in a weird jumps in the audio effects at the beginning of the video. To replicate:

1) Apply the Mastering audio effect to a clip
2) Create some keyframes with initial values for a few parameters
3) Create a second set of keyframes later in the clip that modify those same parameters
4) Create a third set of keyframes modifying those parameters
5) Export the video to h.264 mp4 using Media Encoder

Expected behavior:

Video should contain audio that tweens smoothly between the keyframes.

Observed Behavior:

Audio track starts with the values specified in the third set of keyframes, then jumps abruptly to the values in the second set of keyframes when playback reaches that point in the video. Keyframes after this seem to work normally.

Workaround:

Reset the status of the job in the queue and re-render the video. Media Encoder will only honor the keyframes in the audio track the second time you render that job.

This workaround is annoying because you must render the job twice to get one proper video.