When you say wifi connection you mean the ethernet connection? Mine works fine, what is good because when pressing play in my phone the amp switches on automatically, i don't even need to reach to the remoteSorry, I have not tried the Hegel H90 with headphones and I have to agree the pre-outs on the Hegel seem weak. I also notice the wifi connection on the Hegel H90 is relatively poor so I use the USB input to connect the computer and that works absolutely great.
I tried connecting the Hegel H90 to the Revel F328Be instead of my BMRs. It was a disaster. In this case, the Purifi amp provided an abundance of power while the Hegel H90 would distort at relatively low volume levels. It wasn't pretty. The longer I own the H90 the more I understand it's short comings (wifi/pre-outs). It may not work well with larger speakers. But if you find a good speaker match while using the USB input it can sing.