JBLhttps://ca.jbl.com > warranty
Unless a different warranty period is stated in the Warranty Card provided with your JBL product, JBL warrants for a period of 1 year (5 years for any non- ...
Troubleshooting help
https://www.ifixit.com/Wiki/JBL_Charge_4_Troubleshooting
JBL Charge 4 TroubleshootingiFixithttps://www.ifixit.com > Wiki > JBL_Charge_4_Troub...Make sure the charging light on the base of the device is blinking. If it is fully charged and still not turning on, the power button may be worn out or broken. The Speaker Will Not Power... · The Device Won't Connect to.....
Hi,
it's sound like you've done your best and from my pov, you're not missing anything but just need to get the subwoofer repaired by the manufacturer or completely replaced.
Thank you.
that humming sound 60Hz is a hint of short. inside
it needs to be repaired in a shop.
a shop can fix it.
you have no tools or parts or tech skills to fix it inside.
right? so get it to a shop
or buy the service manual and have at it.
find the short. (top cause bad CAPS)
You are right about the caps. if the unit has a seperate power supply it would be better to replace it, you may also have trouble getting into the case if it is sealed well. It could also be a bad diode etc.
Check the internet connection. The television can't update if it can't see the internet. Resetting it breaks the previous settings.
Just for fun, reboot the router as well and wait 15 minutes until all the lights come back on. Then reestablish the television connection to the router.
Harwa is not a make we know here in North America.
https://www.google.com/search?q=Harwa+Smart+television.+How+to+restore+Apps
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