PreventStandby INTERVAL set to 30 instead of 60 (meaning all "minutes" last 30 seconds

05/09/2012 16:07:38 BST  Assertions          	PID 62705(pmset) Created NoIdleSleepAssertion "pmset prevent sleep" 00:00:05  id:0x100000c69 Aggregate:0x100242	
05/09/2012 16:09:32 BST  Assertions          	PID 62705(pmset) Released NoIdleSleepAssertion "pmset prevent sleep" 00:01:59  id:0x100000c69 Aggregate:0x100240	
Sleep/Wakes since boot:238   Dark Wake Count in this sleep cycle:0

Time stamp                Domain              	Message                                                                    	Duration  	Delay     
==========                ======              	=======                                                                    	========  	=====     
UUID: CF8A17FD-930A-40BE-BCBF-878ACEA161BE
05/09/2012 16:23:22 BST  Sleep               	Idle Sleep Sleep: Using AC                                                 	130 secs  
05/09/2012 16:23:22 BST  SlowResponse        	Kernel: Response from powerd is slow                                       	          	25010 ms  	
05/09/2012 16:23:22 BST  Assertions          	PID 56(apsd) Released ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 01:27:30  id:0xc00000c0a Aggregate:0x101240	
05/09/2012 16:23:32 BST  SlowResponse        	PMConnection: Response from mDNSResponder is slow (powercaps:0x0)          	          	10008 ms  	
05/09/2012 16:23:32 BST  WakeRequests        	Clients requested wake events: [proc=mDNSResponder request=Maintenance inDelta=6471] 	
05/09/2012 16:23:32 BST  WakeRequests        	PM scheduled RTC wake event: MaintenanceImmediate inDelta=6471.00          	

16:25+ Powered on lounge SB and started playing My Music, leading to:

05/09/2012 16:25:32 BST  DarkWake            	DarkWake due to GIGE: Using AC                                             	506 secs  
05/09/2012 16:25:32 BST  Assertions          	PID 18(powerd) Created PreventSystemSleep "PM configd - network wake delay" 00:00:00  id:0x800000c8a Aggregate:0x110340	
05/09/2012 16:25:56 BST  Assertions          	PID 56(apsd) Created ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 00:00:07  id:0xc00000c9b Aggregate:0x111340	
05/09/2012 16:26:02 BST  Assertions          	PID 18(powerd) Released PreventSystemSleep "PM configd - network wake delay" 00:00:30  id:0x800000c8a Aggregate:0x101242	

pmset sets assertion just after powers releases its assertion - but still prevents sleep and playing continues. 

05/09/2012 16:26:05 BST  Assertions          	PID 70173(pmset) Created NoIdleSleepAssertion "pmset prevent sleep" 00:00:07  id:0x100000ca4 Aggregate:0x101242	
05/09/2012 16:26:09 BST  Assertions          	PID 56(apsd) TimedOut ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 00:00:20  id:0xc00000c9b Aggregate:0x101242	
05/09/2012 16:26:09 BST  Assertions          	Summary- Aggregate:0x100242 Using AC

16:31+ Stopped playing and turned SB off
                                       	
05/09/2012 16:33:58 BST  Assertions          	PID 70173(pmset) Released NoIdleSleepAssertion "pmset prevent sleep" 00:07:59  id:0x100000ca4 Aggregate:0x100240	
Sleep/Wakes since boot:239   Dark Wake Count in this sleep cycle:1

Time stamp                Domain              	Message                                                                    	Duration  	Delay     
==========                ======              	=======                                                                    	========  	=====     
UUID: 51DDF5D3-922F-44A0-A7DC-2DA019F39AC8
05/09/2012 16:33:58 BST  Sleep               	Idle Sleep Sleep: Using AC                                                 	127 secs  
05/09/2012 16:33:58 BST  SlowResponse        	Kernel: Response from powerd is slow                                       	          	10012 ms  	
05/09/2012 16:33:58 BST  Assertions          	PID 56(apsd) Released ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 00:08:08  id:0xc00000c9b Aggregate:0x101240	
05/09/2012 16:34:23 BST  Timedout            	PMConnection: Response from AirPort configd plug-in timed out (powercaps:0x0)	          	25014 ms  	
05/09/2012 16:34:23 BST  WakeRequests        	Clients requested wake events: [proc=mDNSResponder request=Maintenance inDelta=6455] 	
05/09/2012 16:34:23 BST  WakeRequests        	PM scheduled RTC wake event: MaintenanceImmediate inDelta=6455.07 

16:36 Powered on Lounge again and started playing
         	
05/09/2012 16:36:05 BST  DarkWake            	DarkWake due to GIGE: Using AC                                             	324 secs  
05/09/2012 16:36:05 BST  Assertions          	PID 18(powerd) Created PreventSystemSleep "PM configd - network wake delay" 00:00:00  id:0x800000ca6 Aggregate:0x110340	
05/09/2012 16:36:26 BST  Assertions          	PID 56(apsd) Created ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 00:00:05  id:0xc00000cb5 Aggregate:0x111340	
05/09/2012 16:36:35 BST  Assertions          	PID 18(powerd) Released PreventSystemSleep "PM configd - network wake delay" 00:00:30  id:0x800000ca6 Aggregate:0x101240	
05/09/2012 16:36:41 BST  Assertions          	PID 56(apsd) TimedOut ApplePushServiceTask "com.apple.apsd-waitingformessages-push.apple.com" 00:00:20  id:0xc00000cb5 Aggregate:0x101242	
05/09/2012 16:36:41 BST  Assertions          	Summary- Aggregate:0x100242 Using AC

again, pmset sets assertion just after powers releases its assertion - but still prevents sleep and playing continues
                                       	
05/09/2012 16:36:43 BST  Assertions          	PID 74257(pmset) Created NoIdleSleepAssertion "pmset prevent sleep" 00:00:07  id:0x100000cbe Aggregate:0x100242	

16:41 Hit key on keyboard to look at this log

05/09/2012 16:41:29 BST  Wake                	DarkWake to FullWake due to HID Activity: Using AC