Support live broadcasting with Ogg Vorbis at 96kHz samplerate

[RJ Skerry-Ryan]

See Bug #686212 for more information. Ogg Vorbis doesn't support 96kHz samplerates, so we need to downsample to 48kHz or something.

[RJ Skerry-Ryan (rryan)]

I dug into this a bit and found that libvorbis works fine with 96kHz in VBR mode but in managed bitrate mode (what we use for encoding) it still does not support this.

Replacing:
int ret = vorbis_encode_init(&m_vinfo, 2, samplerate, -1, bitrate*1000, -1);
with
int ret = vorbis_encode_init_vbr(&m_vinfo, 2, samplerate, 1.0);

makes 96kHz work fine.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/6053