# Crackly sound



## Cainam (May 25, 2004)

I have recently acquired a second Tivo which had a broken modem. I have fitted the cachecard from my other Tivo, and it makes it daily calls without a problem now, so I am using it for a few days to check it all works OK before giving it to a relative. 

But I have noticed something though that I have never seen on my original Tivo. It was all working fine, and I was watching a recording, when I put it on Pause for a few minutes. Occasionally I could hear a "crackling" noise coming through one of the TV speakers. It was not a constant noice, it would be quiet for 20 seconds or so, then a few seconds of crackle, then silent again, and so on.

I checked all the connections were secure, tried different Scart cable, tried a different Scart socket in the TV, but the sound was still occasionally there.

I then worked out that if I disconnected the Aux source (Sky) the crackling went away.

What I *think* is happening is that some of the sound (certain frequencies or volumes) that are coming in the Aux socket are making their way out onto the TV socket. It is only really noticable when Tivo is quiet e.g. in Pause, or in the main Tivo menu. But now I have noticed it, it is bugging me!

Anybody seen (heard?) this before? Any thoughts on the cause/solution?

Thanks in advance!


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## ColinYounger (Aug 9, 2006)

Is it really crackling, or is it a bleeding of sound?

On an old DVD player once I had a SCART socket that had dirt on the contacts that caused exactly the symptoms you describe.

I used a very fine needle and a screen clean wipe and got stuck in each of the sockets. Works fine to this day.

<pauses for hard-core techies to stop wincing>

While I wouldn't recommend the same solution for you - it could be the same problem. I don't know if there are more modern\safe methods of cleaning those contacts.


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## ...coolstream (Dec 10, 2005)

Does turning down the TiVo output volume have any effect? 

If it doesn't, I'd be prompted to investigate the dirty contacts as sugested above.


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## Automan (Oct 29, 2000)

have you tried a soft reboot of tivo?

Perhaps this relates to the problem of no sound where the audio/video switching chip in tivo does not initialise properly.

Automan.


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## Cainam (May 25, 2004)

> Is it really crackling, or is it a bleeding of sound?


That is hard to answer. I thought it was random crackling initially, but the pattern of the crackle matches speech patterns, if that makes sense. And the crackle goes away if I disconnect the Aux box. It is definitely NOT possible to make words out, so it is not a straightfoward bleeding of the sound.


```
Does turning down the TiVo output volume have any effect?
```
Do you mean the option within the Tivo menu for "TV loudness" with a value from -6db to 6db?
In which case then yes, I think it does go away, but I will need to test it again to make sure!


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## Cainam (May 25, 2004)

Automan said:


> have you tried a soft reboot of tivo?
> 
> Perhaps this relates to the problem of no sound where the audio/video switching chip in tivo does not initialise properly.
> 
> Automan.


I will give that a try later on tonight, as it will be recording something in 5 minites time!


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## ...coolstream (Dec 10, 2005)

Cainam said:


> Do you mean the option within the Tivo menu for "TV loudness" with a value from -6db to 6db?
> In which case then yes, I think it does go away, but I will need to test it again to make sure!


That's the one! In which case, it points more to some kind of bleed through rather than static /dirty connections. Maybe a reboot will fix it or perhaps try a different scart.


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## Cainam (May 25, 2004)

OK, I have done some more testing now.

Leaving the Tivo setting for "TV Audio Level" at 6db I did a warm reboot. During the Silicon Dust loading screen for the cachecard, I could hear the crackly noise, which surprised me...

After Tivo had restarted, turning the "TV Audio Level" to 0 db or less turns down the crackle so I cannot hear it, at +2db I can hear it if I listen hard, +4db or +6db is very noticeable.

I think it does depend on what is coming through the Aux - there is a lot of crackle at the moment with Horizon on BBC2 - lots of music or sound effects maybe?

I have already tried a couple of different scarts from Sky to Aux socket, I will try a different one from Tivo to the TV if this may help?

Failing that I may just leave the Tivo setting at 0db, and turn the TV up...It does make any DVDs sound extremely loud though!

Thanks for everyone's contribution so far, much appreciated! :up:


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## Automan (Oct 29, 2000)

Another idea may be to check the audio out level in the Sky box setup menu.
If set at max perhaps it is a too higher level for tivo input.

It's normally set at mid position.

Automan.


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## ...coolstream (Dec 10, 2005)

I'm glad that you're getting closer to a solution...

Some TVs allow you to adjust the sound input per input source, so you could set TiVo output lower and then boost via the TV or lower the DVD input and keep the TiVo lower.

Maybe your TV can do this?


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## martink0646 (Feb 8, 2005)

I've had exactly the same problem for a few months now & its definately bleed. At first I thought it was my amp but I'm sure it isn't as the same problem occurs using different inputs & nothing else connected to the amp has any problems (2x DVD, 1xDVDR, VCR, PS2, Pace HD STB, HTPC etc.).

I think it's bleed because when I am watching a recording from Now Playing & the TiVo/Freeview box is tuned to a radio channel I can make out the spacing of the words without hearing the individual words so it's possibly bleed from the AUX SCART to the TV SCART. Maybe there is some form of short between the TiVo's SCART's. I don't watch live TV so maybe I should try that first.

I will try turning down TiVo's audio & also try changing/cleaning SCART's when I have time although rooting around the cables fills me with enough dread that I've been putting up with it.

Martin


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## ...coolstream (Dec 10, 2005)

A simple test, although it hasn't been suggested yet, is to 

1-disconnect the AUX input from the TiVo.

2-Then reinsert the AUX cable but disconnect it from its source.

3-Then reconnect the AUX to its source but switch source OFF.

4-Then, with all connections as previously mentioned, switch to a channel that doesn't produce sound (e.g. a setup menu)

5-Then switch the AUX to a live channel.

Following this systematic approach should help pinpoint at which stage the distorted sound appears


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## Cainam (May 25, 2004)

Just thought I would keep this post updated in case anyone else has the same problem.

So, while leaving the Tivo setting at 0db I thought it all seemed OK. And then at one point yesterday evening there was a really nasty screeching noise while I was on the Tivo menu (about 9pm I think). I quickly switched over to Aux to see what it was showing, and there was Terry Wogan playing a violin, producing a really screechy noise. Which kind of proved the point that something on Aux was bleeding into the normal Tivo TV output.

I then took Automan's advice and looked at the volume that Sky was outputting at. It was indeed outputting at 100&#37; so I changed it to 50% or so, and turned Tivo back up to +6db to compensate.

So far no more crackles or other unexpected noises have been heard, but it is early days.

(As an aside, I must admit to it taking many attempts to get the Sky box to change volume. This was caused by (a) not realising that the volume control on the Sky remote controlled the volume on the TV, not what the Sky box itself was outputting; (b) having a SkyEye connected from Tivo to Sky, which sends the backup key every 30 seconds which kept changing menus on me; and (c) Not realising I had to hit "Save Settings" on Sky after changing the volume. In my defense I don't think I have ever used the Sky remote before, as Tivo just does everything  )

Thanks for everyone's help so far, if you are passing the North East at some point I owe you all a beer or two!


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## Cainam (May 25, 2004)

Last night was crackle free as well, so I think everything is OK now.

Thanks again to everyone, especially Automan for coming up with a simple working solution!


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