I'm not familiar with the onkyo you have, does it show up as a renderer in bubble? How do you normally play to it?
The results with bubbleupnp are somewhat confusing, if its WiFi issues it should in theory be worse to your phone/ tablet unless your router has the hardware to dedicate to a few clients. Did you end up grabbing another network cable?
Onkyo manual: http://www.intl.onkyo.com/downloads/manuals/pdf/tx-nr609_manual_e.pdf
In Bubble under Renderer group I can select (A) local renderer and (B) TX-NR 609. If A is selected, under Library group, I can select (1) Serviio or (2) Local media Server. If I select 1, I can access all the tracks on my laptop and play through my phone. If I select 2, I can only access the tracks on my phone and play.
If B was selected then no matter what I select in Library, either 1 or 2, only the tracks on my phone is accessible and can be played. The laptop is still on WiFi- no Ethernet connection. Onkyo connected to TP-Link adapter and Viginmedia Hub also connected to TP-Link adaptor.
While listening to the laptop tracks on my phone-which has no drop-outs, I can play the same tracks on Onkyo (it can see Serviio (User PC, User PC: Will's Laptop and BubbleUPnP Media Server (GT-19300- this is my phone), I select Serviio (via Onkyo remote control) and the same tracks have frequent drop-outs.
If required I could insert screen shots if you need.
Regards
william