How to best create this texture?

[DerMalt]

Hey Guys,
I'm a 3D artist, and don't use Photoshop that often. Mainly just for creating textures from images etc.
I came across a nice texture I got from an paid online course, and I want to recreate this texture in Photoshop myself, to do some changes, and to have my own made texture I can use for commercial projects.

I put some text on top of the texture, because I don’t want to publish a texture, you normally pay for.

The black lines I would just create manually, but I was hoping there is a better, more procedural way for creating the grey squares in the background.

Any ideas?

[c.pfaffenbichler · Accepted solution]

A Brush with Roundness Jitter, Scattering etc. might be an option. 

[c.pfaffenbichler · Accepted solution]

Some lines could also be created using such a Brush and some Filters. 

Making the Pattern seamless would of course make things a little more difficult. 

[DerMalt]

Oh wow. I'm gonna try this later. Thank you very much!

[c.pfaffenbichler]

I forgot to mention that you need a square (or rectangular) Brush tip; but that’s easy to make – create a (large) black square on white, Edit > Define Brush Preset.