Un­tan­gle your FireWire ca­bles from your Thun­der­bolt with our help for ex­ter­nal de­vices

Mac Format - - CONTENTS - by Lloyd Tor­rence

Clear up your con­fu­sion about con­nec­tors

As soon as this hap­pens, open Con­sole and look for a re­cent er­ror about IOUSBHostHIDDe­vice

My USB au­dio sys­tem dis­con­nects from my Mac

QSince up­grad­ing it to El Cap­i­tan, my iMac switches its au­dio out­put spon­ta­neously, from the Bose Com­pan­ion 5 speak­ers con­nected to its USB port back to its in­ter­nal speak­ers. I have to restart the Mac or dis­con­nect and re­con­nect the USB ca­ble in or­der to con­tinue us­ing the ex­ter­nal speak­ers, although some­times they re­con­nect later. My Mac’s hard­ware has been checked, and is healthy. How can I keep my sound sys­tem work­ing?

ASim­i­lar prob­lems have been re­ported with sev­eral other USB au­dio de­vices in El Cap­i­tan, so it seems to be a bug that hasn’t yet been fixed. It ap­pears to oc­cur be­cause the Mac loses con­tact with the speak­ers, as­sumes that they have been dis­con­nected, and then re­verts to nor­mal in­ter­nal au­dio out­put.

You might no­tice a log en­try when this occurs. As soon as it hap­pens, open Con­sole and look for a re­cent er­ror mes­sage in­volv­ing IOUSBHostHIDDe­vice, which would con­firm it.

The best work­around at present seems to be to open Au­dio MIDI Setup tool, check your USB au­dio codec, which is re­spon­si­ble for this out­put, and set it to ‘44100.0 Hz’ and ‘2ch16bit In­te­ger’ out­put. Some users re­port that it helps to leave this app open all the time.

It’s worth comb­ing through your Li­brary fold­ers to root out any old ex­ten­sions or au­dio plug-ins that may have been mi­grated from older soft­ware, as one could be cut­ting in and mess­ing up set­tings. These can be blocked for test­ing by us­ing safe mode: hold ß at the startup sound till you see the Ap­ple logo.

Some peo­ple find their USB-con­nected au­dio de­vices, like these Bose speak­ers, spon­ta­neously dis­con­nect ev­ery so of­ten un­der El Cap­i­tan.

The Au­dio MIDI Setup app, which is bun­dled with OS X in /Ap­pli­ca­tions/Util­i­ties, may be able to over­come glitches in which ex­ter­nal au­dio de­vices spon­ta­neously dis­con­nect.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.