-[NSRunLoop runUntilDate:] consumes 100% CPU - ios

Question

I'm building an application that interfaces with external accessories (thus with the ExternalAccessory framework).
Part of this interfacing is waiting for events to occur on the in/out streams to the external device.
For that, I use a thread, and block it in the NSRunLoop to make sure it keeps waiting for events.
- (void)eventThreadSelector
{
// Setting up the environment
self.session = <got the EASession>;
self.inputStream = [self.session inputStream];
self.inputStream.delegate = self;
[self.inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[self.inputStream open];
self.outputStream = [self.session outputStream];
self.outputStream.delegate = self;
[self.outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[self.outputStream open];
// Waiting for events coming from the NSStreams
while (![[NSThread currentThread] isCancelled]) {
[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:.1]];
}
// When the device is unplugged,
[self.inputStream close];
[self.inputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
self.inputStream.delegate = nil;
self.inputStream = nil;
[self.outputStream close];
[self.outputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
self.outputStream.delegate = nil;
self.outputStream = nil;
self.session = nil;
}
- (void)accessoryDidDisconnect:(EAAccessory *)accessory
{
DDLogVerbose(#"EID: Got accessoryDidDisconnect notification on main thread? %i", [[NSThread currentThread] isMainThread]);
[self.eventThread cancel];
self.eventThread = nil;
}
So far, all of this works great :) But there's one thing I can't wrap my head around.
When I unplug the external device, the processor briefly jumps to 100% and above. I've done a little bit of investigation, and this seems to be linked to the NSRunLoop going nuts. That CPU peak has a negative impact on the UI :(
How can I avoid this processor usage peak?