Mac Mini does not recognize external case with LG Blu Ray Burner

[burgwal]

I recently purchased a Mac Mini. Since I already had an internal blu Ray burner from LG, I also purchased an external (SATA/USB 2) case.
Details:
Blu ray Burner:
http://www.lg.com/us/data-storage/lg-BH10LS30
External Case:
http://www.sabrent.com/category/hard-drive-enclosures/EC-ST5B/

My Mac does not see the drive. Once connected, the tray closes and each time I open it, it closes again. Once closed a couple of seconds, I cannot open it any more. If I (manage to) insert a disc, it does not appear on my Mac Mini. Once I disconnect the USB, the drive remains open or closed.
Toast also does not see the recorder.

Now here is the interesting part. Both the Blu Ray writer and the external case seem to work fine:
1. The LG recorder works fine in a Windows machine. I also upgraded the firmware.
2. The case also seems fine: I have an older LG burner (BH08LS20), however, this one does not recognize empty Blu Ray discs (but does read them and writes DVD and CD). This is the reason I replaced it with the BH10LS30 (which if I am not mistaken is a more recent model). If I connect this "old" BH08LS20 using the external case, the Mac Mini recognizes the drive. So I can read BD/DVD/CD an write DVD/CD. This tells me the external case is also working fine.

Help much appreciated.

 

[Cave Man]

When the drive is connected and powered on, does it appear in System Report > USB?

 

[donlab]

I'm seeing the same issue with my 2012 mini, vantec USB 3 case, and lg blu ray burner. I've figured out a work around but I don't know why it works.

First the case is powered and I turn the power OFF
I connect the USB cable from case to mini. That seems to draw enough power to power the drive as the drive's status light comes on. As soon as the USB is connected I wait maybe 15-20 seconds until the drive light stops blinking and making sounds. Then I turn on the case's power switch. Afterwards the drive will show in system report USB and in toast as a supported burner.

 

[burgwal]

It seems indeed related to the power supply of the external case. Thanks @donlab. Your suggestion does not work for my drive however.

It behaves very strange:
Once I don't connect the USB cable from the case, the tray can be opened and closed. But if the UBS cable is connected (even without it being attached to my mac), the tray closes and keeps closing immediately after I open it.

Even if I touch with my finger the USB port on the back of the case, the tray closes.

Apologies for posting this under the Mac Mini forum. It looks like this is related to the external hardware.

 

[donlab]

here is vantec usb3 5.25 case
http://bit.ly/Vqt71l
LG drive
http://bit.ly/1dRkUeu

We have different drives and different cases but a similar issue. I had to send the first case back because the drive wasn't seen by the OS but one time. The wires connecting the drive to the case seemed to have a bad connection somewhere. Now with this new case I can get the drive to show up as outlined above.

 

[qinsonbans]

that right, The wires connecting the drive to the case seemed to have a bad connection somewhere. Now with this new case I can get the drive to show up as outlined above. thanks

 

[burgwal]

My issue is resolved. The cause seems, as earlier stated, in the power supply of the external case.
I (coincidentally) found out that if I connect the drive and power it on, the drive will keep closing, but if I wait a couple of minutes, the drive will open and my mac will play and write discs.

When waiting for less than 1 or 2 minutes, the drive will either close, or opens and the light will start blinking and the drive will not respond.

When waiting 5 minutes or more, the drive will work properly.

Not sure what causes it, but at least it is solved.

Thanks for the help.