iPod 5th gen iOS 8.4 Wifi connectivity problems.

Since updating my iPod 5th gen to the new iOS 8.4 software, my iPod hasn't been able to connect to wifi properly. The only time it will connect is when I'm standing over my router, whereas my iPhone 5s (which I have not updated to iOS 8,4) will connect just fine. I've already tried restarting the iPod, restarting the network, and restoring the iPod to it's factory settings and starting it as a "new device." None of these options worked. Does anyone have any suggestions as to what I should do? I don't wanna use this Apple Genius thing (I've seen it suggested in other posts), as I'm not looking to spend money (at least not a load of money as I just had the home button repaired and it cost me quite a bit). Is it possible when I had the home button replaced (they also replaced the screen because they broke it upon repairing the button) that the repairman messed something up inside the iPod?