First to answer one question from a few posts back, by losing connection, I meant just that. At least once a day, sometimes several times a day, I would have to completely redo the wifi connection in its setup (after rebooting it) to connect it to wifi. By the way, I DID try an HDMI extender and it made no difference whatsoever.
Second, the thing worked fine for the first 8 weeks or so, then started having the connection problems, just getting worse and worse till it just became completely unusable now after about 6 months of ownership. So I have had it too long, I can't just bring it back.
The other day I purchased an Apple TV. Fingers crossed but so far everything is working perfectly.
Like I've said, I've read many complaints about the Rokus. Not sure if maybe there is a bad batch out there or what, as I do understand they work great for some people. But for me? Nope, never again.
It's certainly possible you have bad hardware. But the fact it was working fine and then started having a problem points to one of two possibilities. First, Roku may have pushed a firmware update that had a problem with wireless connections. I haven't seen other reports like this, so unlikely. The other option is far more likely, and that's wi-fi interference from some other wireless device. Very possibly not even within your own home. It's particularly likely if you are using the 2.4 GHz wireless band, since so many devices use that band.
If your wireless offers the 5 GHz band (not all do) you would likely find a much more reliable signal on that band. The way I make sure which band I connect to is to name my 2.4 and 5 GHz bands with different SSID names. Again, not all routers permit separate names. I've disabled the wireless in my DSL router because it only supports 2.4 GHz, plus it's in the garage, so not the best coverage. Instead I've installed two other routers on my home network, enabled the Wireless Access Point mode, and placed them in better locations in the house. So I have four different SSIDs on my home network, so I can be sure which box and band I am connected to.