Latency in at the lowest and says its .10sec of difference ... But i hear the difference lime crazy

BRM1996
I will unplugg and redo everything but ive done this before with no results... Any possibility my computer isnt strong enough (prosseser, sound card ect.) ?

Impossible to answer, as we don't know anything about your computer.
 
It's a good idea to put all this information in your signature so you won't have to supply the same info over & over again.

My bad, its an acer aspire T

That doesn't really help.  We need processor, memory, etc.  See my sig below for the info needed.

If you're using the Windows native drivers, you will not achieve low latency with those. If you're not sure whether you're using the Focusrite ASIO drivers, which should give low latency, then I recommend contacting Focusrite support. 
 
Don't get discouraged, this is all super-daunting when you're just getting started because you have to be enough of a computer jockey to get things up and running. Once your system is purring along life gets better  
 
 

I have a Scarlett 6i6 and it uses MixControl software to avoid latency problems.  I see that the 2i4 doesn't support MixControl, but it does have a Direct Monitor Mix knob that might help.  I found this on the Focusrite web site:

Can Scarlett MixControl work with the 2i4?

As the 2i4 only has two inputs and 4 outputs, Scarlett MixControl is not necessary for its use; so is not compatible with it. You will need to do all routing in your chosen DAW and if you would like to mix between the direct input signal and the output of your DAW you can use the Direct Monitor Mix knob on the front of the unit.

To change buffer size and sample rate you will need to go to the audio preferences in your DAW (Mac) or access the control panel from the audio preferences in your DAW (PC).

Windows 10 acer aspire T
Processor: AMD A10-7800 Radeon R7, 12 compute cores 4C +8g 3.50GHz
RAM: 8g
1000g storage
Sound comes out of earphones plugging into scarlette 2i4
Mic is a blue yeti pro plugged into scarlette in 2 in ports, left and right

Any ideas to a solution?
P.s i had delay problem when i plugged the mic using usb connection.. Now im plugged in directly into scarlette using 2 xlr cable one for left one for right to get more direct sound from mic but now it has airy weird interference kinda sound ...

Your computer is more than capable, so that's not the issue. Have you downloaded and installed the correct driver from Focusrite for the Scarlett? They do not ship with drivers. You must install from their website. You just need a single XLR cable into one of the channels. Make sure the track you are recording on in SONAR, the input is set to the channel that you are plugged into, and make sure the input echo for the channel is OFF. Plug your headphones direct into the Scarlett and there should be zero delay.
 
 
 

Ok let's start over because there is a lot of "noise" in this thread (no disrespect intended).

You're hooking up your mic correctly, XLR to the Focusrite is fine. You were right to discard the USB connection. If you did not install drivers for your Focusrite yet, go to their website and download the latest ones for your device. After installing them, go into Sonar, hit P to bring up the preferences and make sure the "driver mode" is set to ASIO and your Focusrite ASIO driver is selected. These settings, annoyingly, are in different tabs but you should find everything you need in the top few tabs.

This should make Sonar a lot more responsive, BUT, for recording live instruments, the feature you're really looking for is called "direct monitoring". Sound that you pass through Sonar will always have some delay. While it's possible to get it really low, that requires very good hardware and often a lot of fiddling. For this reason, most soundcards offer some form of "direct monitoring" - a hardware connection between the inputs and outputs. On your device, next to the main volume dial, there is a dial that sets the balance between playback (signal from Sonar, like your previously recorded music) and input (whatever you have plugged into the front inputs). If you want to record with no latency at all you use this dial and set it somewhere in the middle so you can hear both your mic and the playback from Sonar. In this case you TURN OFF input monitoring on your track in Sonar, because then you'd hear your voice twice (once from the input and once from Sonar with a slight delay).

The main drawback of this approach is that you can only hear the direct sound of your voice while you're recording, meaning without any effects you might want to put on it. Of course after it's recorded you can hear any fx you like. If you can live with that it is by far the easiest and most reliable solution.