Seagate FireCuda ST1000LX015 crashed and keeps timing out

[feversec]

New user here.
Coming from replacing a Cooler Master PSU with faulty IDE/SATA outputs that caused the whole PC to shut down, I expected this almost 4 years old Seagate 1TB FireCuda SSHD (ST1000LX015) to be trustworthy - given its optimal SMART values and no error being reported whatsoever - like the other devices exposed to the PSU, when it suddenly crashed and reportedly started timing out while I was listening to music stored in it using VLC.

A quick journal inspection revealed this ATA error at the time of the crash

Code:

Nov 24 12:44:06 user kernel: ata5.00: exception Emask 0x0 SAct 0x90 SErr 0x0 action 0x6 frozen
Nov 24 12:44:06 user kernel: ata5.00: failed command: READ FPDMA QUEUED
Nov 24 12:44:06 user kernel: ata5.00: cmd 60/00:20:48:10:7c/01:00:07:00:00/40 tag 4 ncq dma 131072 in
                                              res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
Nov 24 12:44:06 user kernel: ata5.00: status: { DRDY }
Nov 24 12:44:06 user kernel: ata5.00: failed command: READ FPDMA QUEUED
Nov 24 12:44:06 user kernel: ata5.00: cmd 60/00:38:18:b1:6a/01:00:07:00:00/40 tag 7 ncq dma 131072 in
                                              res 40/00:00:00:00:00/00:00:00:00:00/40 Emask 0x4 (timeout)
Nov 24 12:44:06 user kernel: ata5.00: status: { DRDY }

Followed every ~30 seconds by

Code:

Nov 24 12:44:26 user kernel: ata5: softreset failed (1st FIS failed)
Nov 24 12:44:26 user kernel: ata5: hard resetting link

And occasionally by

Code:

Nov 24 12:46:21 user kernel: ata5.00: qc timeout (cmd 0xec)
Nov 24 12:46:21 user kernel: ata5.00: failed to IDENTIFY (I/O error, err_mask=0x4)
Nov 24 12:46:21 user kernel: ata5.00: revalidation failed (errno=-5)

The disk seems to spin correctly when powered and no suspicious click or screeching sounds can be heard.
Rebooting the machine with the SSHD attached results in an excruciatingly long POST eventually timing out.
Connecting it with a SATA-USB adapter results in both the block device and the sole NTFS partition being correctly read: everything from the sectors size to labels and identifiers is as it should be.
Both mount and smartctl --all result in a time out, with an IDENTIFY error being reported in the latter case.

Can something be done or should I RMA the thing and lose the data I didn't backup?