Light sync is slow

Hi-

I'm trying to get a basic setup working on a RPi3B+ latest Debian. I'm using an input mp3 and/or wav file. The songs play at normal speed, but the light synchronization is slow so it doesn't match up with the music (in the test, I'm running a single outlet to a desk lamp using the 1 GPIO pin through an SSR)-- I'll connect up the other 3 circuits if I can get this one to work. Does anyone have a solution or how to do a better search to ask the right question about speeding up the synch to match the music?

Thanks for your help!

Tad

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