I'm assuming that your reference to DPC implies this is on a Windows platform.
The page documenting Thesycon's DPC Latency Checker Tool http://www.thesycon.de/deu/latency_check.shtml has the following good advice when the driver responsible for DPC latency spikes has been identified:
When you have identified the device
driver which is responsible for the
drop-outs consult the device vendor's
Web site or customer support to find
an update for this driver. If this is
not possible you may decide to keep
the concerned device disabled while
you are using streaming applications.
Clearly, if you must receive the stream via the wireless driver then disabling it is not possible though I'm not clear from your question whether you can just disable autodiscovery and still successfully use the card to receive the stream. Whilst this is a workround it may be the best compromise until the driver is fixed, if it can be. As the Thesycon page points out:
Processing of streaming data in
real-time is a very challenging task
for Windows based applications and
device drivers. This is because by
design Windows is not a real-time
operating system. There is no
guarantee that certain (periodic)
actions can be executed in a timely
If you have not already looked at Thesycon's DPC Latency Checker Tool and your project is on one of its supported platforms and is non-commercial then you consider using it for free to confirm your conclusions. Details of the tool and next steps are in the page hyperlinked above.
One final, obvious, suggestion is to relieve the PC of other work by not running unnecessary processes and ensuring sufficient free RAM may help.