I noticed recently that there was an update to the DCAM-API from Hamamatsu (v20.10.6117) that included updated firmware for the Coaxpress capture cards used with their newer cameras. In our hands this updated firmware seems to have made a huge improvement in overall performance in micro-manager. On our diSPIM, running at high volumetric capture rates (>2 volumes per second) used to cause frames to pile up in the sequence buffer after periodic and short hangs. At the time, I thought this was due to garbage collection and indeed switching to alternate GC’s like the concurrent mark sweep and the G1 GC seemed to help with this. More recently, we noticed some odd issues when running on these GC’s (although I can’t say for sure it was the GC itself that was the source) where acquisitions seemed to miss frames and random frames from the sequence were being inserted repeatedly to fill those gaps. As part of troubleshooting, we updated to the 11/24 nightly for 1.4 and the new DCAM and all of these issues seem to have disappeared. Running at 4 volumes per second (240 FPS) no longer causes frames to pile up in sequence buffer, even with the default GC. Not sure I can fully figure out what’s going on, but the main changes (new nightly, DCAM update) are the likeliest suspects and I don’t think there have been any major changes in the plumbing of the diSPIM plugin / acquisition engine in 1.4 to account for this. Hopefully if anyone has run into similar issues running at high-ish framerates with these cameras, updating DCAM may help.