LOC gain help

I have a 2017 trd sport non jbl and I added a plug and play LOC to stock head unit so I can add amp and sub. The LOC has gains (left,right) when they’re all the way down the sub won’t play so I turned the gains all the way up and backed off a little. Is this correct or how do I know how to adjust the gain? Also I noticed I lost volume after the install, maybe because I don’t have the gain all the way up? Or maybe I turned the gains up too much and it’s drawing too much away from the speakers, I don’t know, need help pls

 

It’s most likely a passive LOC and those are just basic level adjustments, and not actual Gain (even though it may say Gain)

Turn them all the way up and be done with it.

you should not have lost volume after the install though. That one is curious

 

Thank you! And yeah it’s a bit weird, I lost volume with Bluetooth but the radio is fine

 

Turn the Bluetooth volume up on your phone. Got to go for the easy ones first.

Check the Bluetooth level control in the head unit too.