Would an external clock “help” in this signal chain?


My system sounds quite good to my ear. But I did spend a lot of time battling a harsh top end which I seem to be especially sensitive to. It’s now pretty great but I can’t help but wonder ‘what if??’ when I think back to all these components I’ve added and how each added to the overall character. 
 

Specifically I’m considering an external clock (or two?) in this chain. Also curious about using a grounding block. Maybe something else?

Here’s the signal chain:

 

iFi LAN iPurifier (converts signal to fiber optic and back)

RJ45 Cat8

Uptone EtherREGEN

RJ45 Cat8

WiiM Ultra (is this a bottleneck? Thought about Holo Red)

USB 

Singxer SU6

I2S

Gustard R26

XLR 

Tube Pre

XLR

Buckeye Hypex NCx500

Wharfedale Linton 85th

Everything is run through a Synergistic Research Power Cell (scored it used and it still broke the bank).

Either iFi Elite or chinesium linear power supplies. 
Power cords are Viborg. 
Interconnects AudioQuest Cinnamon. 
 

Thank you!

machine7

Funny after following and being involved with this thread we found a $33.00 TP Link Travel TL-WR902AC  Router was superior to any F/O Ether Regen or filtering option. When properly set up and place in your digital chain. Selling all those clocks, re-gens, filter..... 

  https://www.whatsbestforum.com/threads/review-the-best-yet-most-affordable-network-switch-tplink-wr902ac.41708/

What improvements would you like to achieve at this point?  Agree the Wiim is an obvious weak link, and I’d upgrade that rather than worry about an external clock, which would be like putting sporty tires on a Toyota Corolla — sure you can do it and it might be a little better, but it’s still a Corolla.  What preamp are you using, because that’s huge.

I appreciate all the input. A few more details I should have mentioned:

Preamp: Sonic Frontiers Line 2 with 4 fresh JJ gold pin 6922

iFi Elite Power supplies on:

iFi LAN Purifier

Uptown Audio EtherREGEN

Deco Router

eBay/China Linear Power Supply on Singxer SU6

https://ebay.us/m/2CYNRe
“Hifi 30VA Linear Power Supply DC9V 2.5A”

 

I would consider reducing the number of components, and get fewer but better components. E.g., Airgapping is implemented in several components (e.g. my Holo May DAC), so you could get rid of purifier and regen. With all those gizmos, with their power supplies and additional cables, you are inviting problems. The famous KISS principle.  

You could also check for issues with pre vs. post-DAC problems by plugging smart phone in and see whether you hear the same top harshness. It could also be the speakers or the room.