Fix delay rounding issue

Fixes issue #20
Refactor patch according to review suggestions
Merge pull request #21 from pronebird/master

Fix delay rounding issue
Fix build issue "Use of undeclared identifier 'BYTE_SIZE'" when compiling for device with Xcode 6 (beta 4)
Merge pull request #22 from Flipboard/undeclared-byte_size-fix

Fix undeclared 'BYTE_SIZE' in Xcode 6
Merge pull request #3 from Flipboard/master

update