Activating Surround Sound project

I am currently using Arduino for an installation that I am creating for my Final Major Project. At the moment, Arduino is used with a relay to control light and vibration pillow activated by a switch. The final part of this is getting that same switch to activate sound from a DVD player. I have tried a few methods - one being using a IR transmitter and receiver to send signals from the remote but this didn't work with the Surround DVD player. I also thought about opening the remote control up and soldering wires from where the play function is to a relay but there wasn't the opportunity to solder. I am starting to get very concerned about this as I can't think of any other way to activate the surround sound. Any advice would be greatly appreciated!

I have tried a few methods - one being using a IR transmitter and receiver to send signals from the remote but this didn't work with the Surround DVD player.

Why wouldn't this work? Also, each manufacturer has different specs on IR communication for their appliances. I'm not a expert in this, but why don't you use a phone with an IR blaster? That way, you could even make an app to control the Arduino, but you'll have to program an Android.(I know this is overkill!)

Otherwise, you could take said IR blaster phone, fire up the native remote app for controlling stuff, see if your DVD player is there, and use your IR receiver to record the IR pulses for the function required for your DVD player. Then you could transmit them back to the player, when you need it.