iMZ220-MfiBtPrinterConnection::close is slow on IOS10

When we print a simple label from IOS10 device, the print is instant, but [connection close] call takes several seconds to complete. The same code/library/app works without any delay on older IOS8 phones.

 

Sample code for printing:

 

 

(NSInteger) printFormat:(NSString*)formatString error:(NSError **)error

{

      id<ZebraPrinterConnection, NSObject> connection = [[MfiBtPrinterConnection alloc] initWithSerialNumber:[self serialNumber]];

     BOOL success = [connection open]; //instant

     BOOL isConnected = [connection isConnected]; //instant

     NSInteger bytes = [connection write:[formatString dataUsingEncoding:NSUTF8StringEncoding] error:error]; //instant and print is done

     [connection close]; //3-7seconds to close connection!!!

     return bytes;

}