Hi! I've found many different "Media Pending" posts, but haven't found this situation. Every time I open a project in Premiere CC (2015.0.2 release) the bins (icon view) populate with the poster frames on the second monitor (kinda slow). Then shortly the line at the bottom of the primary monitor below the timeline reads the media has completely "loaded".
If I double-click any icon to load a clip the "Media Pending" graphic shows up. Nothing will load. Even the timeline shows Media Pending. If I leave Premiere for about 20 minutes or so then everything is fine. But sometimes after editing all day, all clips will start showing "Media Pending" again and I have to close/reopen Premiere. I did have one serious error crash after opening the project a few days ago. "...ExporterParam.cpp-509", but no serious errors since.
At this point the current project has only cuts with nothing brought in from any other Adobe programs. All footage is H.264 1080p in an MOV wrapper. We have not had these kinds of issues with H.264 previously, though I know a lot of people transcode. The footage plays fine, can shuttle fine in the bins and on the timeline when we are not having the Media Pending issue.
We are currently using a 2015 MacPro, 3.7GHz quad-core with 10MB of L3 cache, 12GB (3x4GB) of 1866MHz DDR3 ECC, 512GB PCIe-based flash storage, Dual AMD FirePro D300 GPUs with 2GB of GDDR5 VRAM each. The latest Yosemite with a thunderbolt Sonnet enclosure housing a Kona LHi, SeriTek eSATA and SCSI cards. Five drive software RAID connected via eSATA. Any thoughts or posts you can recommend? Thanks!!