Dual zoom is triggering Melee

Yep, I've had this happen MANY times as a sniper, I usually need to restart the game to get it to work properly.

Yes, I also had this with the A280 or whatever it is called.  I've noticed that I sometimes accidentally forget I am in infiltration, so the dual zoom doesn't work there, of course.  And the dual zoom melee problem happens some time after I have used infiltration.  So I wonder if the bug is due to your character not leaving infiltration mode properly.  I've noticed the scan dart effect for assault sometimes lingers too long, so I wonder if this is a similar problem with infiltration.  

I have this too on PC with every weapon there is a dual zoom attachment for.
This happens because sometimes when spawning the dual zoom attachment is broken/does not work. Normally there are two dots on the bottom of the scope view telling you in which zoom mode you are, but sometimes they are missing and so you know, that the attachment is broken for this spawn.
Trying to double zoom in that case will result in melee attack, because they share the same keybinding.

A little sporadic, but definitely happening to me also.

Same on XOne, can't seem to find any reason, it just randomly happens then fixes itself, as others mentioned. Happened before 1.2 too, so it's not the new patch's fault.

That happened today to me as well. What I could notice is that it was like dual zoom was not equipped to the weapon. 

I "solved" this issue by respawning and checking if dual zoom was equipped before joining the battlefield again.

Yep, I've had this happen about 50 times, the only way to fix it is for your character to die and restart, or to quit the game and restart.

I don't think EA are going to bother fixing this, it's been happening for months now.