[rendanator]

I recently purchased a Fiio E9k and while I love it, from what I now understand it doesn't disable the line out when headphones are plugged into the front. This wouldn't be a problem, except I can't easily turn off my speakers and subwoofer because the subwoofer is hidden under my desk. What ends up happening is that my speakers and sub keep playing when I plug my headphones in. Here's my setup:
 
                                            -> Line out ->2 RCA Splitters-> M-Audio Av-40 and Polk PSW10
Titanium HD RCA Out-> Fiio E9k:
                                            -> Headphone out -> Sennheiser HD 650
 
Is there an easy way to disable to Line Out with some sort of in line RCA switch? I was also considering putting the sub and the speakers on their own power strip and turning them off together easily, but that still creates the problem of having to fumble around under my desk. 
 
I can also still return the Fiio E9k if anyone has any suggestions for a better amp that can do what I want it too. I'm willing to spend a bit more, but ideally <$200. 
 
Links to relevant products
AV-40: http://www.amazon.com/M-Audio-Studiophile-Powered-Monitor-Speakers/dp/B0051WAM64/ref=sr_1_2?ie=UTF8&qid=1355796267&sr=8-2&keywords=m-audio
E9k: http://www.amazon.com/Output-Desktop-Headphone-Amplifier-Compatible/dp/B008J26ZL4/ref=sr_1_1?ie=UTF8&qid=1355796304&sr=8-1&keywords=e09k
Titanium HD: http://www.amazon.com/Creative-Blaster-Titanium-Internal-SB1270/dp/B0041OUA38/ref=sr_1_1?s=electronics&ie=UTF8&qid=1355796426&sr=1-1&keywords=titanium+hd

 

[rendanator]

I caved and decided to buy a Matrix M-Stage Amp because I heard from other threads that it did indeed mute the output when the headphones were plugged in. There seemed to be some disagreement, does anyone have this amp and can tell me if it functions this way?

 

[Cyborg]

I recently bought a E9K also, and it does not mute the line out when you plug in the headphones. I think there are different versions of the E9K so maybe some of them do mute, but mine(the newer version) does not.