My download is fine at 800+ but my upload won't go above 4 Mbps.

Whole system is as follows: 

ER8411 (v1.0) 1.3.1

SX3008f (v1.2) 1.20.7

SG2428P (v5.2) 5.20.11

2 EAP653 (v1.0) 1.1.3

I have enabled max jumbo and also enabled flow control and that got me an extra 2Mbps on the upload and another 150 on the download.  I can not wrap  my head around what is going on and why it is capping my upload speeds.

I have also started to get an issue where my SX3008f will lose connection to one of my computers at a time, and the only way to resolve the issue is to reboot the router.

Any help would be amazing!