I have seen this before; takes several tries to get it on and gets worse and worse.
All these sets (not just your brand) have a standby power supply that runs 7/24 even if the set is not on; One of the areas these companies cut corners on is filter capacitors in the power supply.
Let us say they hve a unit with a 9 volt standby voltage (it is on all the time) and to save money they put capacitors rated at 10 volts= a tidy savings if you produce 10,000 units and the difference between 10 volt rated caps and 16 or 24 volt rated caps is a nice piece of money.
They do not care as the unit will usually last a year or two and then fail.
The good news is if someone opens the unit (UNPLUGGED FIRST) AND does a visual inspection they will be able to SEE the bad caps.
The caps are perfectly flat on top and the silver material has creases in it: a bad cap can instantly be seen and this is the first thing to look at: see attached photo of the typical type of cap.
I have seen units where anywhere from five to ten caps were bad; same kind of problem occurs in tower type computers; If you shop around the caps are pretty cheap and marked with value and voltage rating along with a minus and plus for positive and negative----each cap only has two leads and are fairly easy to replace.
There is no magic bullet for this: someone has to open the unit and look at the caps.
BEFORE YOU RATE THIS INFORMATION LET ME KNOW WHAT YOU FIND!
SD TECH