LinkStation Pro Quad (LS-QV12TL/R5) rebuild problems

[ejpontius]

I have two of these 12TB Linkstation Pro Quads. They were configured as RAID 5 for 8TB of storage.
One one of the LS I had a hard drive failure years ago and replaced the drive. The array rebuilt and everything was fine. A while later another drive failed. I replaced that drive and began to rebuild the array. The drive is chocked full of 8TB of data (hence the purchase of the 2nd LS) and as such takes a long time to rebuild. I left it overnight only to return the next morning to find the LS offline with a single red solid red light displayed next to the drive #3. I rebooted the LS and it started up seemingly as normal with the blue status light and each of the drives powering up to green. This goes on for a while and then the status light starts to blink amber and it now shows not only the drive I replaced as amber, but an additional drive.
I can access the LS HTML interface and it shows me that these two drives have an error. It shows the array as "not configured".
Thinking that I was just cursed by the gods and happened to have the bad luck of having a 2nd drive fail during the rebuild, I put it aside and accepted my losses.

Just recently the 2nd LS I have started showing me a warning that a drive was failing. By this time this LS is also full with 8TB of data. I replaced the drive, started to rebuild the array and left it overnight. I come in this morning to find a single solid red light on drive 3 and the drive offline. I rebooted the LS. It goes through its start up, blinks blue status, shows green drive lights and then the status light starts blinking amber and it shows an amber light for the drive I replaced and a 2nd drive. The HTML interface shows
I'm thinking that I can't possibly have had the same bad luck twice of coincidentally having a 2nd drive (also drive 3) fail during the rebuild of the array and that this must be some software hiccup.
Is there any possibility that this can be fixed? The RAID in both these cases were working in degraded mode prior to this. The drives appear to be mechanically sound.