Just had track rods replaced (that needed doing), hoping that an annoying knocking noise would go away, alas it hasn’t.

 

noise seems to be coming from the front of the car, perhaps underneath the centre console somewhere

All sorts of things can knock

When running, not running etc.

Mine knocks from the DMF due to mileage as I've done 140k but was doing it at 80k. That is clear it goes away when you put clutch in.

So more clues might help

The knocking occurs on rough country roads as opposed to dusl carriageways and motorway 

ARB bushes or drop links.

Top mount bearings can cause noise.

I'd personally start with drop links. £25 a pair and 10 mins a side to change. 

Have a look at the anti roll bar bushes, grab the bar and give it a good tug/shake. If you need to, use a heel bar to see if you have excessive movement. The drop links are easily accessed, so you'd notice quite easily if they're the problem or not.