Hey folks. I'm trying to correct the weak signal from my
receiver's mono out to the sub. With a line level connection it's extremely weak and only somewhat improved with a Y connector. The only way I've been able to get any decent output is with speaker level connections. I have a pretty old 5.1 receiver (Onkyo TX SV424). Curiously, the remote has center/rear adjustment buttons, but nothing for fronts/sub. What gives?