So, I have a wac7500 and twonky 4.4.x on a maxtor mss2 nas. I have suffered intermittent 'connection interrupted' messages, artist/index feature doesn't work above 4.4.2 and I get the usual 'unknown artist' display during playback. Although these features worked on my ps3 and xbox360 no problem
I bought a licences and opened a ticket. After 2 weeks, yes 2 weeks, I got an email saying my case was open and I would be contacted shortly. After 6 more weeks I have still heard nothing, even having mailed twonky support since.
So I gave up on twonky and looked for another solution. I settled with m ediatomb, which is free/opensource. Now my menus on my wac7500 seem faster, I can search in a more uniform manner, artist index works and wait for it ... I do NOT get unknown artist anymore. So to all those people that say it's a WAC bug ... if it is, m ediatomb works around it. Still no album art yet.
Now my wac7500 streams reliably and I haven't had to reboot it in a few weeks ! All I can say is try it out
So now I need to figure out how to get a refund on my twonky license.