Mac Mini Fan Running Constantly

Fairly new to Mac so still lots to learn...

I have a 2-month old Mac mini that doesn't get used all that much so far but It's always been totally silent. I'm doing an initial backup to an online backup service and the latest batch of files has been backing up since Tuesday night so I'm staying away from that computer mostly.

This morning I checked the progress of the backup and I noticed that my iTunes icon was jumping and there was a message hidden under the backup window "The iTunes Library file cannot be saved. An unknown error occurred (35)." I left that as is figuring I'd deal with it tonight when I have more time.

When I stopped home at lunch time to check the backup status I heard a loud hissing sound coming from the direction of the Mini. As I got closer I realized it was coming from within the mini and I'm guessing it's a fan (which I never knew the mini had). When I opened the iTunes window I saw the spinning beachball - and figured it had probably been doing so since whenever the "error 35" began.

I was unable to click anything in iTunes - needed to Force Quit. When I did that, the fan stopped and the Mini became silent again but the top/bottom were noticeably warmer than usual.

I've been backing up at various times from the Mini and never heard the fan and never felt the top/bottom heating up. I use it standing on it's side with plenty about an inch of space on either side for ventilation.

Any idea what might be going on? Is there, in fact, a fan inside the late 2012 Mac Mini? an could the spin up of the fan be related to the iTunes Error 35 and the spinning beachball?

First... all Mac machines have fans. Without a fan (if it should stop because of a defect) to cool the CPU and related heat sink in your Mini, the machine would shut down.

Backing up to an on line service can take days depending of course on the amount of data you have, so it's likely the machine is going to have to work harder. The iTunes error probably caused a loop to occur and forced the CPU to run hotter. That in turn makes the fan spin faster and becomes noticeably loud.

You should have stopped the backup when the iTunes error happened instead of leaving it. You need to resolve the library error first before proceeding with the backup.

chscag said:

You should have stopped the backup when the iTunes error happened instead of leaving it. You need to resolve the library error first before proceeding with the backup.

Click to expand...

First, my apologies for not getting back here sooner to acknowledge your reply. It's been a very hectic month with lots of data issues and moving data between 5 different drives before getting things under control.

I believe the iTunes library issue (if there really is one) was unrelated to the other drive issues because iTunes and Dropbox are pretty much the only data that I store on the Mini's hard drive. Everything else is on external drives and it appears that the problems were related to two twin external drives.

Unfortunately, that morning when I first noticed the iTunes error I was rushing to get to a meeting on time and was not thinking clearly. I didn't think iTunes being unable to save a file would have any affect on the computer or on the backup. So I left the error message on the screen for me to deal with later. The backup did, in fact, eventually complete without any error reported.

I've since installed iSystatus on both the Mini and MBP so that i can at least have some idea of what the temperature typically is and I have not heard the fan again since that day.

I still don't know what caused the Error 35 for iTunes or if there's any lasting impact on the iTunes library. iTunes seems to be working fine.

FWIW, the issues that caused me so much grief last month that eventually led me to two new USB drives were frequent Error 36 situations (unable to read or write a portion of a file) while copying / moving large amounts of data from one external drive to another or to/from the hard drive. There was never anything wrong with the file referenced by the error message. In every case I was able to manually drag the file by itself to where I needed it to be. But it eventually became a tedious folder by folder move.