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Simon Turner
2004-03-07, 12:13
I don't think it is a buffer problem as it empties instantly and refills
instantly. I did think it was a Windows/WiFi problem, but now I am not too
sure.
I have realised that whenever the drop outs occurr the Squeezebox becomes
entirely unresponsive to the remote. I've no idea what this indicates, but
feel that it is probably indicative......
:-)

Simon Turner
Brighton UK


> -----Original Message-----
> From: discuss-bounces (AT) lists (DOT) slimdevices.com
> [mailto:discuss-bounces (AT) lists (DOT) slimdevices.com]On Behalf Of Stuart
> Hickinbottom
> Sent: 07 March 2004 17:29
> To: Slim Devices Discussion
> Subject: [slim] Squeezebox: Sound drop out with Flac files
>
>
> Thanks for the information; it might be true that the speed of the WLAN
> prevents effective streaming in such a raw format, but I would have
> expected to have been able to see the buffer draining down to an
> eventual
> drop-out point if this was the case. However, like Simon, I see
> the buffer
> permanently full until, suddenly, it drops to zero and the sound
> drops out
> for a few seconds.
>
> Perhaps this is a feature of the size of the buffer in the
> Squeezebox (I'm
> not sure how large it is) draining inbetween screen updates? I
> don't know
> how long the internal buffer would play raw data before draining the
> buffer when it is not being filled.
>
> Stuart
>
> On Sun, 7 Mar 2004 10:56:25 -0600, Andrew W. Donoho <awd (AT) ddg (DOT) com> wrote:
>
> > Simon and Stuart,
> >
> > FLAC, like AAC, decodes to either WAV or AIFF. This consumes a great
> > deal more bandwidth than an MP3 that is decoded in the SqueezeBox (1.5
> > Mb/s versus 320 kb/s for highest quality MP3).
> >
> > One thing you can do to minimize retransmissions on wireless is to
> > disable WEP security. WEP security can chew up a significant amount of
> > your approximately 6 Mb/s of real wireless bandwidth (upwards of 20% or
> > more). In Simon's case, a 40% signal strength is also a cause of
> > retransmissions. I recommend that he try to get his signal strength up
> > by repositioning his base station/AP.
> >
> > Andrew
> >
> >
> > On Mar 7, 2004, at 10:08, Stuart Hickinbottom wrote:
> >
> >> I, too, have experienced this. At first I thought it might be a
> >> problem in the encoded FLACs, but replaying them causes drops in
> >> different places thus ruling out this possibility.
> >>
> >> I've checked the server and it's definitely not working hard either in
> >> terms of network, CPU or disk activity.
> >>
> >> I have the Squeezebox operating over the wireless and so I wondered
> >> whether that was a factor. The Squeezebox indicates about 60% signal
> >> strength, which might be relevant, but if it wasn't able to stream
> >> fast enough I would have expected a gradual drain being visible on the
> >> buffer meter, which is not the case (it suddenly drops to zero once
> >> the player goes silent).
> >>
> >> I've configured SlimServer to encode to MP3, via LAME, when streaming
> >> FLACs over the internet. I don't experience this problem via this
> >> channel, which makes me think that the FLAC decoding is working
> >> perfectly and it's just something to do with the SlimServer/Squeezebox
> >> route when playing FLACs.
> >>
> >> I too am using v5.1.1 with firmware 8, although I'm using a Linux
> >> server.
> >>
> >> Hope that's enough information to be helpful. I'm not even sure I want
> >> to encode everything as FLACs (192kbit MP3s sound nice enough to me),
> >> so this isn't necessarily a big deal for me.
> >>
> >> Stuart
> >>
> >>
> >> On Sun, 7 Mar 2004 10:31:23 -0000, Simon Turner <simon (AT) brighton (DOT) co.uk>
> >> wrote:
> >>
> >>> Every now and again (av once per song perhaps) I'll get a second or
> >>> two of
> >>> silnec during a song. I have the Progress Indicator set to Show Buffer
> >>> Fullness and can see that the buffer momentarily (and very instantly)
> >>> drops
> >>> from it's usual constant full position to zero.
> >>>
> >>> This does not happen when I play MP3s (even v. hi quality rips
> >>> e.g --alt-extreme or 320CBR), It only happens when I play Flacs (I
> >>> don't use
> >>> any other formats).
> >>>
> >>> These are my particulars:
> >>> Squeezebox. Firmware 8.
> >>> SlimServer 5.1.1
> >>> Windows XP
> >>> Wireless signal strength 42%
> >>>
> >>> Condition of PC - RAM and processing power very underutilised. Minimal
> >>> number of other services running.
> >>>
> >>> Any suggestions very welcome
> >>> Thanks
> >>> Simon Turner
> >>> Brighton UK
> >>>
> >>>
> >>>

Daryle A. Tilroe
2004-03-07, 21:53
Simon Turner wrote:
> I don't think it is a buffer problem as it empties instantly and refills
> instantly. I did think it was a Windows/WiFi problem, but now I am not too
> sure.
> I have realised that whenever the drop outs occurr the Squeezebox becomes
> entirely unresponsive to the remote. I've no idea what this indicates, but
> feel that it is probably indicative......

There was some discussion of these various issues of bandwidth and buffers
in the previous 'Native FLAC' thread. I have experienced the odd similar
symptom but assumed they would disappear if I hooked up ethernet. Instead,
since FLAC to the SB seems imminent, I am hoping these issues will all
become moot in a month or two.

FWIW 40% seems to be on the ragged edge for WAV/PCM streaming over wireless
to the SB; that also assumes all WEP, etc. is turned off.

Just how large is the SB buffer? 10kB? 100kB? 1MB? If it is on the lower
end the buffer would probably empty before any visual display has time to
update. Once this occurs I believe there is a bug somewhere with the
co-ordinating of process/communications between the slimserver, flac.exe,
and the SB; this could cause an intermittent hang.

--
Daryle A. Tilroe

Daryle A. Tilroe
2004-03-08, 19:01
Daryle A. Tilroe wrote:

> FWIW 40% seems to be on the ragged edge for WAV/PCM streaming over wireless
> to the SB; that also assumes all WEP, etc. is turned off.

After some testing I can confirm that with %40-%50 signal my microwave
kills the stream with WAV/PCM audio. I get the signal strength going
completely random down to as low a 0. A nice interference device. Then
the stream dies. A lot of the time it recovers once the microwave is off
but sometimes it just hangs and requires you to press <play>. Sometimes
even that doesn't work and nuking the playlist and then adding new songs
seems to work. I would seem to me that some more study of how the
server and SqueezeBox recover from an interrupted, externally transcoded/
decoded stream may need to be done. Oh also the slimserver then seems
to need a manual reload or its display is stuck on the song where the
stream was interrupted.

> Just how large is the SB buffer? 10kB? 100kB? 1MB? If it is on the lower

Anyone???

--
Daryle A. Tilroe