Thanks Thierry for this advice. Yes I was aware of this. Actually, the data were obtained by analysing videos frame by frame. The video's resolution was such that each frame "duration" is considered to be 0.04s. My first advice to the biologists was to use the numbers of frames for both number of success and failure. They did not want this because they want to speak (and analyse) in term of real duration. Hence, using ms instead of frames is multiplying the number of attemps by 4.
It seems more like a set of different time-series (one for each video) with (0,1) data at each point (frame within video) rather than one observation per video. So some random effects to model video and time? Auto-correlation (does that work in a logistic GLMM?)? Random (video) intercepts? Plus some other stuff. Ron.