I normally don't use LFI Player but I did use it to verify that the DAC works since it is the only application I have access to that supports the EtherDream DAC. I only used it for 10 seconds or so to confirm that it works... and it did provide laser output. I didn't use it long enough to see if it crashes, however. Contact me offline if there is something you would like me to try.
At this point I am leaning strongly towards writing my own native driver for it that communicates with it using raw networking. Certain APIs in the Etherdream.DLL infinitely hang at certain points so the DLL isn't production ready. I am thinking of creating a separate thread on this forum to document my work and to get input from other developers who are attempting to interface with the EtherDream DAC.
The EtherDream website says that LSX and ILD-SOS use a native driver instead of the DLL which makes me wonder if that is why people don't complain about it when using those applications but when trying to integrate with it using their own code or using LFI Player they have issues. The website goes on to say to contact DrLava for a copy of the Open DAC SDK if you want to have that native driver but that really isn't an option for me since that would be a conflict of interest. Hopefully, the source code on GitHub and the protocol documentation on the Ethernet website is current and accurate enough to write my own driver. If all else fails I'll just sell the EtherDream to the highest bidder.
Best of luck!