Other sound problems
If you've only got sound problems on one channel, there's probably a problem with the broadcaster rather than your Sky box. Try again later to see if the problem's fixed.
Loose cables can cause sound problems. Check both ends of your HDMI or AV cable to make sure it's securely connected to both your TV and your Sky Q or Sky Q Mini box.
If you’re still having problems, try another HDMI socket on your TV.
If using a soundbar or a home cinema system, try disconnecting your other device and connecting your HDMI cable directly to your Sky Q or Sky Q Mini box instead. If that fixes your problem, there’s likely an issue with the device you disconnected and you’ll need to contact the manufacturer for more help.
If you're still having problems, you'll need to order a replacement Sky Q box.