As I understand it, the arcade ROM intentionally ended scenes too soon to account for laserdisc seek latency. The dle11 and dle21 ROMs fix this scene cropping, but as a result makes it less like the arcade experience.
How are you adding the latency parameter?
Yes, Dragon’s Lair.
See this log text. The 6th line is in the command line (also “-latency 950” is on the wiki) and the 16th line sets latency to 950 milliseconds, then at the bottom there are warnings that latency isn’t working .