Whenever the pulse of the timer activates the sound creates about a tick of lag

I have this exact same issue! It's on a modified pack based on DW20 1.7.10 with Project Red removed and BluePower added. I am going to try connecting to the server it's on with a few different Minecraft installs. I'll let you know how it goes.

That's probably because the sound gets played on the server and it takes some time for it to sync with the client, will take a look at it tomorrow

Nope, all client side, no packets are sent. I'm guessing the problem doesn't lie with the sounds. To be sure, disable gate sounds in the config and check again?

doesn't help, doesn't play sound but still causes a moment of lag

I think the gate's pointer display is faster, the sounds and output are correct.

I get a slight FPS drop, but apart from that I can't reproduce the 'tick lag'... Also I don't think we can really fix it.