使用process.waitForExit()时线程被中止错误

下面的代码是从while循环中调用的,所以它在一行中执行了多次。有时,但并非总是,我最终得到的线程在p.waitforexit()上被中止错误。有人对此有什么见解吗?我应该在p.waitforexit之后调用p.close()吗?

string outputFileName = Path.Combine(Path.GetDirectoryName(recordingFileName), Guid.NewGuid() + ".mpg");
        ProcessStartInfo startInfo = new ProcessStartInfo(ffmpegfileName);
        startInfo.Arguments = "-i \"" + recordingFileName + "\" -r 30 -sameq \"" + outputFileName + "\"";
        startInfo.WindowStyle = ProcessWindowStyle.Hidden;
        Process p = Process.Start(startInfo);
        p.WaitForExit();
        if (p.ExitCode != 0)
        {
            throw new Exception("exited with an exit code of " + p.ExitCode.ToString(CultureInfo.InvariantCulture) + ".");
        }
        return outputFileName;

Thread was being aborted.
mscorlib
 at System.Threading.WaitHandle.WaitOneNative(SafeWaitHandle waitHandle, UInt32 millisecondsTimeout, Boolean hasThreadAffinity, Boolean exitContext)
 at System.Threading.WaitHandle.WaitOne(Int64 timeout, Boolean exitContext)
 at System.Diagnostics.Process.WaitForExit(Int32 milliseconds)
 at System.Diagnostics.Process.WaitForExit()