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rfrost
2010-05-17, 14:02
I'm almost embarrassed to ask this question, as I've been an SB user for >3 years now, but here goes...

I'm finding that on my SB3, when playing .flac and .m4a (Apple lossless?) files, I get stalling on the SB3, as it'll stall, and say, "Rebuffering… XX%" Where actually is the stall happening, on my slimbox or on the server? My server is a fairly robust Intel Pentium fellow ("Prescott" CPU) running a well-hacked and very stable version of OSX. I also have a SB Touch (and LOVE it!), but I've not noticed if that stalls as well.

So where's the rub, and how might I remedy it?

Thanks in advance.

Phil Leigh
2010-05-17, 14:14
I'm almost embarrassed to ask this question, as I've been an SB user for >3 years now, but here goes...

I'm finding that on my SB3, when playing .flac and .m4a (Apple lossless?) files, I get stalling on the SB3, as it'll stall, and say, "Rebuffering… XX%" Where actually is the stall happening, on my slimbox or on the server? My server is a fairly robust Intel Pentium fellow ("Prescott" CPU) running a well-hacked and very stable version of OSX. I also have a SB Touch (and LOVE it!), but I've not noticed if that stalls as well.

So where's the rub, and how might I remedy it?

Thanks in advance.

wired or wireless? - looks like a wireless problem...

snarlydwarf
2010-05-17, 14:15
I'm almost embarrassed to ask this question, as I've been an SB user for >3 years now, but here goes...

I'm finding that on my SB3, when playing .flac and .m4a (Apple lossless?) files, I get stalling on the SB3, as it'll stall, and say, "Rebuffering… XX%" Where actually is the stall happening, on my slimbox or on the server? My server is a fairly robust Intel Pentium fellow ("Prescott" CPU) running a well-hacked and very stable version of OSX. I also have a SB Touch (and LOVE it!), but I've not noticed if that stalls as well.

So where's the rub, and how might I remedy it?

Thanks in advance.

Flac isn't transcoded normally (there are exceptions, like if you deliberately force it to do so, or are using a SliMP3 or SB1 which doesn't support FLAC natively).

It sounds more like your problem is between SBS (which doesn't do a whole lot of work to send a FLAC, no more than it does for mp3), and your SB: ie, your network.

Is this wireless? Is the server itself wireless, too? That will use twice as much available bandwidth as just one wireless hop, and if your usable bandwidth is low due to noise, a flac could push it over the edge. (m4a's are transcoded on the server, and sent as flac, but since flac itself is being jerky, I don't think your problem is transcoding, but transmission.)

JJZolx
2010-05-17, 14:16
Transcoding happens on the server. FLAC, though, isn't transcoded unless you've changed some advanced settings - it's streamed as-is to both the SB3 and Touch. Sounds like your problems are most likely to be with your network. Are the players connected wirelessly?

rfrost
2010-05-17, 15:54
Sorry, Phil, I should have specified.

rfrost
2010-05-17, 16:16
So the emerging consensus is that it's a network issue; I'll check that thoroughly, as I've had problems on that leg of the network in the past. It just seems odd that I'd get a slowing rather than an all/none result, as is usual in the digital world. Yet more digging in dusty areas to check the switches…

That said, I do worry that in trying on my [lame] own to solve this, I diddled with the "File Types" pane of the Server Prefs (which, I daresay, has an oddly opaque UI) and got something wrong. For the FLAC option, I've set it with the FLAC stream format as Native, with the MP3 as faad/lame, and with the PCM as flac. FYI, for AAC, I have the AAC stream as Native, the FLAC stream as faad/flac, the MP3 stream as faad/lame, and the PCM stream as faad. Also for Apple Lossless, I have the FLAC stream as faad/sox, the MP3 stream as faad/lame, and the PCM stream as faad. Are those correct?

[I suppose that this isn't the appropriate place to gripe about Apple's determination to put ever-more proprietary file formats out there. What's so wrong with flac that we needed Apple Lossless as an alternative? And I say this as an Apple person of 25 years!]

Thanks so much for your help thus far. I'll post whatever resolution I achieve.

JJZolx
2010-05-17, 16:35
So the emerging consensus is that it's a network issue; I'll check that thoroughly, as I've had problems on that leg of the network in the past. It just seems odd that I'd get a slowing rather than an all/none result, as is usual in the digital world. Yet more digging in dusty areas to check the switches…

Slowing is often very much the problem with wireless issues. First, the wireless connection will commonly be renegotiated to a slower speed when the signal is weak or interference is encountered.

Second, there's the relationship between wireless network throughput over some time period and buffer size on the player. You might encounter enough interference to completely shut down the network connection, allowing the buffer to run out, then it may clear for a moment, then back again and so on. Whether you see dropouts and a 'rebuffering' message will depend mostly on whether the network can keep the buffer filled just enough to avoid the dropouts. That's why streaming MP3 will sometimes give you continuous playback, when streaming FLAC fails. The same buffer that holds 30 seconds of FLAC audio might hold 2 minutes of MP3 audio.

pfarrell
2010-05-17, 18:04
JJZolx wrote:
> That's why streaming MP3 instead of FLAC will often gain you continuous
> playback - the same buffer that holds 30 seconds of FLAC audio might
> hold 2 minutes of MP3 audio.

This is 100% true. Back when the SB1 was current and it used 802.11b,
you could often find that you could not reliably steam FLAC files.
Actually the SB1 didn't support FLAC itself, so when you had FLAC, you
actually sent PCM/Wav over the network. So a 2 minutes of MP3 would be
15 seconds of PCM. The solution then was to use Cat5. The SB2 improved
things in two ways, first, it supported FLAC decoding locally, so you
sent only 50% as many bytes, and second, it had twice the memory buffer,
so you had a net gain for four times the buffer for FLAC.

Even today, MP3 is a lot easier on marginal WiFi setups than FLAC.

--
Pat Farrell
http://www.pfarrell.com/

Phil Leigh
2010-05-18, 10:39
Sorry, Phil, I should have specified.

Whoah - rebuffering on a WIRED connection? - packet collision?... or something else on the network eating the bandwidth?

What version of SBS are you running?

snarlydwarf
2010-05-18, 10:57
Whoah - rebuffering on a WIRED connection? - packet collision?... or something else on the network eating the bandwidth?

What version of SBS are you running?

Or bad cabling job.

In my former office, well, okay, so that was 12 years ago... the phone guy did the wiring.. It wasn't even Cat3: he twisted the pairs wrong. Instead of TX+/TX- and RX+/RX-, making balanced pairs, his wiring was TX- and RX-, TX+ and RX+ ... instead of a balanced pair that is designed to reduce interference, he actually created interference. It -mostly- worked until there was enough utilization to make the packet loss/retransmit noticable and the network would die a nasty death.

rfrost
2010-05-24, 07:43
Seems that you (collectively) had it pretty much right all along. Turns out to have been a network switch. I replaced it and it now runs like a champ!

Thanks to all.