Sorry for not getting back here on this sooner, had a crazy few weeks of work.
I installed only the WLAN Atheros 9.0.0.202 W7x64 drivers. Latency still occurs but much much less than before. These are the best drivers for the W-LAN card so far.
DPC Latency still has spikes, but not enough to cause repeated stuttering or popping in the audio or video. The sound glitch will only occur if DPC latency spikes to or above 16000us. I have been testing the laptop extensively and it has been running beautifully.