It always happens at the worst possible moment, doesn’t it? You’re booked solid, working 10 hour days, borderline zombie, and the program you use the most starts acting funny for no reason, and apparently no one else in the world has ever shared the same problems (or so Google tells me).
I’ve recently come across a host of Flash audio problems and feel I’ve come up with some fairly straight forward solutions. One side note just FYI is that all audio used was professionally recorded, so none of the issues from what I can tell were caused by the quality of the initial recording.
Problem #1: My audio file sounds slow and drawn out, like a dying record
While adding in .wav audio into a project, it took me a while to realize it, but the VO (Voice Over) actors all sounded a lot deeper voiced that I’d assumed was natural. A few hours into the project I needed to edit a clip of audio and opened it into my favorite editing tool, Adobe Audition (earlier known as Cool Edit Pro before being bought out). Lo and behold the VO actor’s voice sounded clear and natural, the way it should. So what was Flash doing to my file?
Solution #1: Batch process or save your files at a different sampling rate
Now this may be a no brainer for all you audio editing geniuses out there, but for a Flash developer like me who only dabbles in the complexities of professional audio recording, it took a while and some digging to figure this out.
To correct this problem, re-sample your files down to 44100 HZ or a lower quality 22050 HZ. Flash likes these two sampling rates the best which is the important part. You can do 44100 HZ, 16 bit Mono, or 44100 HZ, 32 bit Stereo, it’s the sample rate that matters and will fix the problem.
Problem #2: My audio file appears to randomly skip the first .75 to 1 second of audio in my file
This was a new one on me. I’ve had audio files cut out in the middle for no apparent reason, but to have a batch of 20 perfectly edited .mp3 files, and on import say 5 of them appear to skip the first second or so when playing back. Very odd! It didn’t matter if I put it on streaming, speech or event sound, and when I opened the audio file in Audition it played back perfectly fine.
Solution #2: Add some silence
Keep in mind this is a hack and doesn’t explain why Flash is acting up, nor does it really solve the problem, but it does work! After a few hours of frustration, I decided to add about .75 seconds of silence to the beginning of my skipping audio files. This was done in Adobe Audition, and I simply saved over the original file and kept the same file format and sampling rate. I then updated my file (or re-imported it) into Flash and there you go… problem solved. The file would no longer skip the first word.
Problem #3: My sound quality varies even though all my files are from the same recording session
I am, importing correctly sampled .mp3 audio files, when every once in a while, I’ll come across a random file that just sounds muffled and degraded for no apparent reason. I go back to Adobe Audition and check the source file, which always ends up being perfect and clear, but back in Flash it sounds like it was recorded on a Fisher Price microphone.
Solution #3: Tweak then re-save the file
I found the simplest way to fix this, was to open up the .mp3 in Adobe Audition, add the slightest bit of silence to the beginning of the audio file (like .1 seconds), then save over the original. I then updated or re-imported my audio file back into flash and amazingly, the audio quality is perfect and crisp.
Problem #4: My .FLA files are HUGE after importing my audio
Most people could care less about the size of their source .FLA files, but when you’re like me and make backups nightly, or have to zip and ftp source files around the globe, large file sizes are a huge pain.
Solution #4: Batch your .wav files into .mp3 files before importing
Unless you could care less about file size and set your sound export settings to RAW (uncompressed), you are most likely compressing your imported Flash audio to .mp3 format whether you know it or not. The trick to not only reducing your source file size, but also getting the best possible sound quality out of Flash is to set your sample rates and file types to exactly match your Flash audio export settings. Why? For one you can cut about 50% of your file size off .FLAs by using .mp3. And secondly, when you let Flash do the compressing for you, you might get some sketchy low quality results. By pre-sampling and compressing, you basically tell Flash to back off and not touch your audio files.
Problem #5: I like to mix Event sound and Streaming sound on various occasions, but the audio quality never sounds the same when using the two settings side by side
When you deal with a lot of VO audio, there are plenty of situations where you need both a mix of streaming sound and event sound.
To explain the difference, streaming sound is permanently glued to the timeline, and will play frame by frame when you scroll the scrub head through your .FLA file. If you need to time something precisely (like lip syncing, a music video, animations) this is the setting for you.
Event sound on the other hand, will play an entire audio file, even if the audio is sitting on a single key frame. This is great for sound effect triggers, button sounds, quiz responses, and any situation where you need to cram a lot of audio into a relatively short timeline.
The problem is, even if you set both export settings (there’s one for streaming, and one for event sounds) to the same sample rate, they both come out sounding entirely different.
It ends up that Event sounds are higher quality in nature than streaming sounds, so how do you blend the two together to get a seamless quality sound?
Solution #5: Set your streaming export to “MP3 80HZ – Quality Best”
Simple right? Just bump up (reduce) the compression. I don’t know why Event sound is so much more crisp… something to do with the file calling an instance from the library as opposed to permanently mapping the audio to the timeline (as in streaming). The “problem” is that I’d usually assume that 32HZ Streaming would result in the same quality sound as 32HZ Event, but not so.
Well, that does it. I’ve run out of audio problems. If anyone knows of any other Flash audio issues and would like me to take a look or add the solution to this post, shoot me an email!
