@Shigeru_Lloyd In theory, if Satellite Deco can't connect to Main Deco, it'll try to connect to another Satellite Deco. I wonder if something is up with new M4 you bought. Try this: 1. Place 'new' M4...

@Napalmo0 This switch should be compatible. Reminder: your setup will only work with Deco in Access Point mode, I would suggest connecting Satellite Deco to the switch only after you configured Deco...

@Vassilis Set password for Guest Network exactly the same as it is for Main Network. If Redmi won't connect to Guest Network after that, take careful look at password and special symbols in it. Start...

@36ty That means Satellite Deco can use both bands for devices that try to connect to it. The next step would be to promote Satellite to Main Deco, swap Deco units and see if problem moves with Deco...

@HeinvL I can offer you a workaround for about $50. What you will need: 1. Two very short Ethernet cables, Cat 5E or Cat 6, that work with M5. Test them by bringing third M5 to where second M5 is and...

@36ty Something might be wrong with Satellite Deco, even if Deco app says everything is OK. Open Satellite Deco page in Deco app and check what it shows under "Connected to:" Example, with Satellite...