Question

I am using a embeddable Flash based MP3 player (The standalone Version of WordPress Audio Player, to be exact) to play audio on the web page of a client. Given the nature of Flash based players – AFAIK they all use Flash’s audio/video decoding libraries – the exact player product might not matter, though.

She complains that some specific audio files sometimes tend to play slowly, as if on a tape deck that doesn’t run at full speed. Her machine is a 5 year old Sony Vaio with a 1.5 GhZ Pentium M Processor, so it’s not top of the line anymore but it should not have trouble decoding anything, let alone a MP3 audio stream.

I can’t verify the problem because we can’t set up an audio connection (slow Internet on a remote island), nor can I reproduce it on my 3.3 GhZ dual-code Workstation, but this is a person whose error reports have seldom turned out unfounded in the past, so I tend to take them seriously.

I see differences between the encodings of the MP3 files (see below).

My question: Has anybody ever experienced something like this?
If yes, what was the reason?
If it’s something in the encoding (which I suspect), could somebody give me pointers towards which setting(s) to change?

This is what Winamp tells me about a file that is sometimes slow:

MPEG-1 Layer 3
128 Kbit, approx. 966 frames
48000Hz Stereo

CRC: Yes, Copyright: No

This is what Winamp tells me about a file that is never slow:

Encoder delay: 576, Zero Padding: 1584
MPEG-1 Layer 3
151 Kbit (VBR), 12405 Frames
44100Hz Joint Stereo

CRC: No, Copyright: No

Answer 1

I think this is a bug with certain versions of the Flash player. I have a Flash-based MP3 audio player that I made with the same problem. The solution is to make sure it is a 44,100 kHz MP3 file… or make your users upgrade their player.

Here is my site with the details:

http://web.archive.org/web/20111227184112/http://www.quickmediasolutions.com/sandbox/audio_player/