Yes...Replace the diode...
sorry to say I believe its damaged or flawed causing it to multi-mode, especially that much...
What you are seeing is it hopping between modes..those snaps back and forth...
When I test my diodes ..I use a photodetector and run it to an audio amp and listen to the beam ..tells many stories..if it is quiet..then there is no hopping..
Sometimes,..you can control it by finding the correct current to make it stop that and at the same time be at the right wavelength...most 808 diodes used are not multi-mode..they are single but every once in a while one will slip out of production flawed..Hard to see it being IR and all...
if they are you'de be seeing fat or multiple beams after conversion to green!!!
Reason I believe this is because I have run into this many times..and just changing the diode made it go away...
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