I'm no expert on this, but the audio out can provide both analog and digital output, and there's a little microswitch hidden inside the socket. If that switch gets accidentally changed, audio fails. There is a little light in there which indicates one or the other modes, but I'm not sure which is which.
Hope this gives you something to look into. However, given that the internal speakers also don't work, it could be hardware. Rob On 13/04/12 10:53 AM, cm wrote: > Hi Tim, > > You could be experiencing a hardware failure. I know it is always a surprise > when hardware fails, but when software fixes doggedly refuse to work it is > indicative of possible hardware problems. > > If you have an external drive, you could try a clean install of any > compatible version of OS X either Snow Leopard or Lion. If the clean install > refused to drive the speakers and your SMC and PRAM have been reset it's hard > to think what else could be causing the problem. > > Cheers, > Carlo > > On 13/04/2012, at 9:50 , Tim Law wrote: > >> Hi, >> >> I have an intel Mac Mini late 2009 running under Lion. >> >> For the last month or so I have not been able to run the external speakers >> that I plug into the headphone socket on the Mac Mini. i.e. no sound comes >> out. >> >> I can use a set of headphones that are connected via a USB port. >> >> I have also noticed that the internal speaker does not work. >> >> Having said that, the internal speaker did work last week, but not this >> week. I moved the computer, clearly upsetting the fung schway?? spelling. >> >> What I have done. >> Following the advice on various forums I deleted the preference files >> com.apple.audio.AudioMIDISetup.plist >> com.apple.audio.AudioMIDISetup.plist.lockfile >> com.apple.soundpref.plist >> >> >> I notice these have not automatically recreated themselves after a restart, >> so I reinstated them from a backup. >> >> I reset the SMC by removing the power cord, holding the power button for 5 >> seconds, releasing the power button, reinserting the power cord and >> restarting. >> I had a little heart attack when the Mac Mini restarted with a folder >> containing a question mark, but DiskWarrior rectified that and all is back >> to normal. >> >> However, none of this has fixed the audio problem. >> >> I would like to be able to play sound from the external speakers and would >> like my computer to be running properly. Anyone found a solution to this, >> not uncommon problem? >> >> Tim >> >> >> >> -- The WA Macintosh User Group Mailing List -- >> Archives -<http://www.wamug.org.au/mailinglist/archives.shtml> >> Guidelines -<http://www.wamug.org.au/mailinglist/guidelines.shtml> >> Settings& Unsubscribe >> -<http://lists.wamug.org.au/listinfo/wamug.org.au-wamug> > -- The WA Macintosh User Group Mailing List -- > Archives -<http://www.wamug.org.au/mailinglist/archives.shtml> > Guidelines -<http://www.wamug.org.au/mailinglist/guidelines.shtml> > Settings& Unsubscribe > -<http://lists.wamug.org.au/listinfo/wamug.org.au-wamug> > -- Associate Professor Rob Phillips Educational Development Unit Room 4.42 Level 4 Library North Wing, Murdoch University r.phill...@murdoch.edu.au Phone: +61 8 9360 6054 Mobile: 0416 065 054 Life member, Australasian Society for Computers in Learning in Tertiary Education Fellow, Higher Education Research and Development Society of Australasia Recent book: Evaluating e-learning: Guiding research and practice http://www.routledge.com/9780415881944/ -- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Settings & Unsubscribe - <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug>
