Do you have any audio going when you put it to sleep? Also is the audio not working from the speakers, headphones, or both when you wake it up? There is definitely an issue in the Mavericks kernel relating to audio. It has been documented many times and hopefully will be fixed in 10.9.2. Check Activity Monitor to see if there is a process called kernel_task using 100% CPU. Also open Terminal and run the command "sudo powermetrics" without quotes to see the current hardware usage on your computer. You'll have to scroll through it but you'll see a section that looks like this:
If one of your cores (most likely CPU 0) has a task called (HDEF) with interrupts in the tens of thousands, chances are it's the same kernel bug as HDEF is related to internal audio.
**** Interrupt distribution ****
CPU 0:
Vector 0x46(SMC): 1.00 interrupts/sec
Vector 0x72(IGPU): 9.79 interrupts/sec
Vector 0x74(XHC1): 122.26 interrupts/sec
Vector 0x79(ARPT): 22.97 interrupts/sec
Vector 0xdd(TMR): 208.17 interrupts/sec
Vector 0xde(IPI): 43.55 interrupts/sec
CPU 1:
Vector 0xdd(TMR): 19.58 interrupts/sec
Vector 0xde(IPI): 18.58 interrupts/sec
CPU 2:
Vector 0xdd(TMR): 89.70 interrupts/sec
Vector 0xde(IPI): 53.14 interrupts/sec
CPU 3:
Vector 0xdd(TMR): 15.58 interrupts/sec
Vector 0xde(IPI): 18.98 interrupts/sec
Nope nothing.
The audio doesn't work from both, but when I unplug headphones and close the laptop, then reopen, log back in and put the head phones back in, it works?! The only kernel task in activity monitor is only using 2.5% of CPU.