I'm using a Mac Pro (Late 2013) w/ Xeon E5 CPU on Sierra Version 10.12.4. The disc drive is a Sonnet Echo 15 Thunderbolt Dock. The actual drive within the dock is a MATSHITA BD-MLT UJ260AF. I've burned CD's/DVD's using Finder in the past and had similar issues, but those were easily resolved by disconnecting the disc drive. Now I need to burn BD's, so I'm using Toast Titanium 15 to do that. A BD image is stuck and is causing Finder to lock up entirely when trying to eject the disc, open Toast, or insert another disc. Basically any time I interact with the drive at all, Finder stops working and is causing severe problems. I've spent all day trying to resolve this and have gotten nowhere, so here we go. I have this stuck on my desktop and in the Finder sidebar: - If I so much as click on the desktop icon, my cursor starts spinning and never stops. The first time it happened, I walked away from the computer, went to lunch, and came back an hour later to see that it was still unresponsive. - I have tried dragging the icon to the trash. It becomes translucent and stays in place, never leaving. Cursor usually spins endlessly too. - Clicking the Eject button on the sidebar makes turns the icon grey but it stays there and the desktop icon stays. Finder becomes unresponsive. - Dragging the icon off of the sidebar turns the icon grey, leaves it there, makes Finder become unresponsive. - Unplugging the disc drive does not make either icon go away - If I turn on the computer with no drive connected, the icons are not there and the computer runs normally. If I plug in the disc drive, both icons come back and the same problems persist if I interact with it in any way. I have tried two other disc drives (neither are docks, just regular USB disc drives) and the issue is the same. - I have tried force closing and relaunching Finder. The Mac OS UI will disappear, my desktop will stay in place, and Finder will never come back, no matter how long I wait. - I have tried shutting the computer down via Apple menu. This makes the screen go black but the computer stays on and never shuts off. I tried leaving it this way over night and found it still on with a black screen the next day. - I tried logging out of my user account. The screen went black and hung there, the same way it did when I tried shutting the computer down. - Nothing other than holding the power button/unplugging the computer will turn the computer off when this happens - I tried running Apple hardware diagnostics, and no problems were reported. - I tried uninstalling Toast and deleting all Toast data. The issue persists. - Toast will launch and operate normally if I open it after turning on the computer with no drive connected. After the drive is plugged in, the offending icons return and Toast locks up, giving me the spinning wheel of death forever. Launching Toast while the icons are on the desktop/sidebar causes Toast and Finder both to become unresponsive. Force quitting Toast will make the program close, but the program will not reopen after that. My cursor will continue to be a pinwheel during all of this. - The disc in question was burned using Toast Titanium 15 about two weeks ago. I have burned over 20 discs since then with no issue. I have no idea why this is happening now or why this specific disc keeps coming back. - If I right click on Toast in the Dock, it shows the name of the disc in the tray. Clicking on that makes Finder and Toast unresponsive. This is absolutely insane. I can't understand why this disc keeps coming back or how to get rid of it. There is no reason why this machine should have should have so much trouble with a single disc. I can't even come up with an explanation for why it chose this particular disc to haunt me, as it wasn't the first or last disc that I burned using Toast. What am I missing here? What can I do to make this problem stop, and better yet, how can I prevent it? Thanks for your time.