Having trouble setting up a HomePod stereo pair

Some things you can try:

• The homepods might have updated to the latest software 12.3, Did you also update your iOS device yet? If not, do that and check both HomePods are on 12.3
• Unplug the homepods for a few seconds 
• lift the homepods off the surface and rock them gently to recalibrate. When they think they got moved, they adjust
• try asking them to play music to all, both of everywhere - this may get them back in sync
• Use another app: Go to a different app on your device which uses HomePod and see if it pairs. This may restore sync.
• Try swapping left and right - back and forth a few times.
• On the iOS device that you use to set up HomePod, make sure that you signed in to iCloud with your Apple ID and turned on iCloud Keychain. You also need to have two-factor authentication set up for your Apple ID.
• Make sure that your iOS device has Bluetooth turned on and is connected to your home Wi-Fi network.*
• Reboot your wifi router
• Make sure that the Home app and Apple Music app are installed on your iOS device. If you deleted either of these apps, go to the App Store and redownload them.

• If they still don’t work:

  you can also sign out of iCloud in the home app , then sign back in 

  check your internet connection and unplug the router for a minute to reboot it,

• repeat the ungrouping process 
• manually remove both from the Home app and set up again  (you must Ungroup first) 
• https://support.apple.com/en-ca/HT208244

you set them up and used the stereo pair setting and what? They aren’t playing in sync?