POE ports 5-8 NO POWER

[PapaBill]

Ok I bought a refurbished nvr, REP-NV4108E-HS
I have been playing hell trying to get my cams back up, and finally got one to work but the other 3 ports all make the cam light flash rapidly instead of solid when I plug my cams in,
I tried using a new cam with the net cable provided from amcrest and it does the same on the 4 ports, either flashing fast or very rapidly.
When I try to plug it onto the ports 5-8... NOTHING HAPPENS. totally blacked pout power.
I replaced a cat cable on one outside cam and got it to work then moved the plug over and stopped working, but now got it back and leaving it.
But I still have 4 ports that are dead.
Is this a bad refurb or me?
I wanted to ask before I send it back
Thanx for any help.

[PapaBill]

Forgot to mention that on ports 1-4 the cam light is literally doing a strobe effect.
#3 is the only one that a cam works in atm

[Revo2Maxx]

Sounds like a dead NVR, if power supply issue my guess no camera would power up.

Either bad cables or bad machine, one camera that works with cable being used test other ports of NVR, if not working need new machine