Is there anything to help using a computer from digital noise not that expensive

I have all good  quality Ethernet cables cables and USB cables , but coming out of my computer i I have a Ether regen  coming into the computer ,nice clear signal from the router, I have been told on the computers other end noise from theUSB out from the computer ,Sonore wants $1500 , these littlejitter bugs ,and Ifi audio are worthless.

my system sounds good under the circumstance , but I am out of work for a year with a cervical fusion operation , monies are tight , if anyone knows of anything please chime in I  have my $$ expensive usb coming out from the computer into the dac . Uptone used to make something but parts no longer available ,

thanks Much.