Can someone help me. I've beaten Brayko, and I let him live but when I go to my safehouse all that is there is Braykos Knife, and I cannot find the stereo anywhere?  
 
I actually killed him the first time, but then went on youtube to listen to the song that was playing, and found out if you let him live you got his stereo so I reloaded an older safe and redid the mission to let him live, just for the stereo! Whereabouts is the stereo located and does it only unlock later on? 
 
Hope someone can help me, I really want that stereo!

I never delved into the various possibilities in Alpha Protocol, but I'm in the same boat - I didn't kill Brayko, got the coke knife but I've never heard of receiving his stereo.
 
I just looked up Brayko on an Alpha Protocol wiki and it seems it exists. Supposedly if you take the money he offers and let him live it will be delivered to your Moscow Safehouse.

" @RedBullRacer: make sure you took his bribe and let him live you are able to let him live without getting his stereo if you go down a certain wayit's a hard decision because I can listen to that song over and over again well i used to before i had to do that fucking boss battle over and over again  "

figured out a BIG issue with this tonight.

basically, when brayko is offering the stereo and money, if you reply with the professional response, you'll talk about surkov again, which seems like a repeat of what they'd just talked about. HOWEVER, if you reply in the "casual" manner, you'll have a joke and brayko will talk about his sister. THIS will unlock the stereo if you then accept his deal. Had to figure this out tonight as the stereo wasn't unlocking for me, until i had done this.