How to turn off Voice Control in iPhone 5s? It keeps interrupting my work randomly.

Voice Control of my iPhone 5s keeps on activating and interrupting everything that i try to do. Even when phone is locked, no headphones connected, just laying on table or in my pocket, it starts doing random stuff (playing music, asking to call someone etc). I searched all day on all Apple forums and internet groups and here is what I found out:

1- Apparently, this is a very frequent and BIG problem throughout iPhone users around the world, but somehow Apple guys have managed to just ignore this issue since many years (Since iOS4 till iOS8).
2- The best "solution" suggested by other users is to enable Siri (as it overrides Voice Control) and then turning Siri access off while on lock. So now the phone is good for as long as it is locked. However, whenever i start doing anything after unlocking, Siri starts interrupting me instead of Voice Control. So it seems that the only solution is to choose between these two devils.

3- Majority iPhone users have not ever faced or even heard of this issue and this is not anywhere among "common problems faced and their solutions" on iPhone help sites. However, I feel like it is being ignored on purpose, as there is no permanent viable solution. I am saying this because if you just copy/paste my question on internet, you will find out how globally wide-spread this issue actually is.

So, the good people of internet and tech genius of Apple, if anyone can solve my problem I would be really very thankful. Any suggestions, other than what I wrote in point#2 ?