4 channel amp wiring - sub and 2 speakers

[roon_VR]

hello all,

im having some trouble wiring 2 speakers and a sub. This amp that i have seems to be generic (got it for free). It has two sets of RCA inputs (2x2 red and white) and i have 1 set of RCAs coming out of the headunit. I've been fiddling around with it and i can only seem to get either the two speakers playing no working sub, sub playing and one speaker playing but the other muted. i've bridged channels 3 and 4 for the sub and channels 1 and 2 for the speakers. i was wondering, do i need another set of RCAs coming out of the headunit so it plays the 2 speakers and sub all together?

thanks

[azzfox]

you will need an RCA splitter.

[roon_VR]

thanks for that