Hegel H300 still worth getting?

Hegel is nice and a quality product for sure but it's a little laid back, I used to own the H30 and was always looking for the volume knob but you can kick it in the pants a bit with some super revealing IC's which helps or a AC cable with some pop. The Higher end Nordost stuff for example could work well if you like that sound. Don't use Cardas or the like or anything warm unless your speakers are super revealing then you maybe good to go as is. 

It's not the DLNA causing the problem. That is as stable a platform as their is.

The problem is elsewhere, router, switch, service, cables, etc...

or it sounds like you need set a larger buffer via audionirvana


USB from Macbook is total garbage and Airplay is even worse garbage and I say this not to be critical at all but to help you out.

Ethernet is by far superior to either of those. If you must use USB and many prefer this then do yourself a favor and pick up a cheap used microRendu and a power it with a cheap used Uptone LPS and it will be 1,000 times better but better yet iron out that Ethernet DLNA because Ethernet is vastly superior. Like 100 to 1 better. Good luck...