Don't take the knock sensors signal lightly. I had the same issue, after reading some guys saying that it might be a false signal, I didn't take it to serious. My engine blew due to knock. It's costing me an arm and a leg to fix it!
If it's knocking, GET IT FIXED! There's nothing more serious, It won't be long before you break a ring land.
The knock sensors do occasionally give out a false signal, but if it's happening often then more than likely your engine is knocking
Back off the timing a few degrees
If you can't access a tuner, go on youtube, type in power fc tuning, there's a good video on how to do it.
If I remember right, it was some guy with an rx7 that posted it on YouTube
If you can't find the vid, shoot me a msg and I'll find it for you