If there are no issues with performance on a wired connection, but clear issues on wireless, then there are two solutions:
1) Improve your wifi signal - that's opens up a pandora box and depends on your home router. I guess you're using the Wi-Fi router provided by COX? You could probably get a local electrical or low-power cabling company and run the Ethernet cable in the walls with nice wall terminations.
2) You could get an inexpensive NAS from Synology. 1 bay if you want to minimize the spend, or two bays (or more) - then you could mirror drives in case one fails and not lose your entire collection due to one failed hd.
I generally dislike that Synology NAS typically uses older, cheaper internal components, but the important bit here is that the software is best in the industry. Something like DS223j should do the trick to be a DLNA server for your home. If you put an alert on Keepa.com, the NAS goes on sale somewhat regularly at $150-$170, if you're willing to wait. Another "fun" issue is that the hard drive prices nowadays are astronomical, thx for AI datacenters.
See the article with step-by-step instructions:
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