TT24 Constantly Turning Off and Re Booting

If anyone is still reading this forum and ha0 experienced the desk initially booting as expected then after about (say) 45 secs it down powers then about 5 secs later it re boots for possibly about 15 secs then repeats the shutting down re-booting process continually.
I am presuming that it is a power supply problem (possibly a failed capacitor), but does anyone know for certain what the problem is.
Any advice would be greatly appreciated.
Also has anyone had any experience with the onboard effects not working --- I am presumimg that it is going to be a dirty ribbon cable as the desk has not been used for a number of years and when I collected it the desk was set up on a table in a some what dirty country shed.
A dirty cable could also possibly be the cause of the power switching problem.
Any advice on both matters will be greatly appreciated.
David
I am presuming that it is a power supply problem (possibly a failed capacitor), but does anyone know for certain what the problem is.
Any advice would be greatly appreciated.
Also has anyone had any experience with the onboard effects not working --- I am presumimg that it is going to be a dirty ribbon cable as the desk has not been used for a number of years and when I collected it the desk was set up on a table in a some what dirty country shed.
A dirty cable could also possibly be the cause of the power switching problem.
Any advice on both matters will be greatly appreciated.
David