Btw,if you are really that broke, another method you can try is checking if this only occurs at lower rpm. Try slightly loading the engine but bring the rpm up with light throttle position and see if it still ticks. The higher the engine rpm the more resistant your engine will be to detonation.
As stated the video is nearly impossible to identify the issue due to vibration. Detonation generally sounds like marbles, and will occur under a slightly rich condition and/or with your timing advanced too much for the engine configuration. Richen the mixture, see if that helps. I used to think it was a loose bolt in the engine bay....silly me.
Let me know what you find.
Walker