The ROLLS MB15b PROMATCH works well.The product is built well.The Power plug going into the Rolls Promatch connects well, holds in there tight.- - - - - - - -I'm using this with RCA 'LFE .1' connection (From preamp/receiver) - to the promatch - to - Balanced connection on sub.- - - - - - - -Besides that,- My setup personally, I had issue getting my sub to turn on properly or stay on at lower volume or bass amount.- I'm sure it's not the sub, but The solution for me is to Turn the level on the sub itself down a bit (+6db to 0db or a bit lower(MONOLITH M-10 V2 SUB)) and adjust the level on the ROLLS MB15b accordingly to what you need to make it work properly.It's Something to do with the auto on/off feature that I want / need to use.- At higher volume there is no issues seeing it's a lot more signal, so I Could essentially go ' +6dB ' on the sub level itself, and whatever level on the ROLLS MB15b, but for me in this room it's not about turning it up to 11 all the time, I want Balance in my room with the Bass and the speakers + the room. .. & be able to have audio at lower volume without losing the signal to my sub...I hope this info helps anyone having any issue or problem getting their sub to work with the ROLLS MB15b.** Additionally - I'm currently keeping the level on my ROLLS MB15b between 11 - 1 o'clock 'turn' .. depending on what I want at that time, and/or what I'm listening to, it's simple and works.** In my Current situation / setup I Don't think I will need or want to turn the level up a lot more, as it will be off balance with the setup/speakers.. And just be too much.Great Product! :)Good Luck with your setup.