Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.
Sorry to hear you're having trouble.
Unfortunately, the symptoms you are experiencing are symptomatic of an internal hardware defect, typically a faulty power supply or main board (the 2 most common failure points). This issue could be a manufacturing defect, but is also often caused by a power event (shock/surge, prolonged over/under voltage condition, etc) which we see very often. It could also simply be age related wear and tear. These units are basically mini computers, and set top boxes like this have so many electronics packed into such a small space, along with a constantly moving hard drive, that they tend to have short lifespans. For a 5 year old unit, it has exceeded it's service life already. What I would suspect is that either the drive has failed, preventing the unit from booting, or that the video output card has failed.
There is one step you can take here, both as a possible fix, as well as a diagnostic evaluation
1) Unplug the power cord from the mains, as well as all connections to tv and cable/aerial feed.
2) Wait at least 1 hour (60+ Minutes)
3) Press and hold the power button (on the unit, not the remote) for 60 seconds
4) Keep holding power button while plugging back in, and for another 60 seconds after. When plugging back in, go directly to the wall outlet, bypassing any power strips or surge protectors.
If this reset process does not work, it would unfortunately confirm a hardware failure.
At that point, it is time to replace the system. This unit is not worth fixing, as you'd spend more on parts and labor than you would to replace the entire unit. You could expect to spend about 300 on parts and labor, while you could buy a brand new unit with a much larger drive as well as updated features and a fresh warranty, for the same price or less.
Here is one I'd recommend if you want a DVR only (no dvd recorder):
Panasonic DMR-HWT130EB Smart 500GB (click for link)
And one if you want dvr + dvd recorder:
LG RHT599H 500GB HDD (click for link)