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slimmac
2012-03-24, 07:59
Hello,

I'm experiencing issues with a Squeezebox Touch connected to a Rotel 1570 when the sampling/bit rate of sources switch.

I have a SqueezeBox Touch connected via digital toslink directly to the Rotel (I've also tried coax digital).There is no analog connection made.

Whenever I play a 96Khz or 88Khz 24 bit source, and then select a 16Bit 44.1 KHz redbook source/song, the song becomes distorted. Its very low and garbled in sound.
I can always play 44.1 to 88 or 96 with no issues. However, if I play a Hi-RES file then a 44.1Khz file, the audio is low and highly distorted

This occurs with either a Wav or FLAC file.

All songs are being played on the SqueezeBox connected to the same input BTY. I've tried different inputs on the Rotel - same issue. The only way I can get the audio back, is to power down the Rotel and restart or switch the inputs on the Rotel.

So....initially it appeared to be the fault of the Rotel DAC's. HOWEVER....If I take the same files, and play them through my Oppo bluray player, connected using the same cable and input to my Rotel, all is well....So the issue is stemming from the SBT. The files play perfectly from the USB key.

I'm using the following Software and firmware versions on a Mac OS 10.7.2 tower with 14GB of RAM:

Logitech Media Server Version: 7.7.1 - r33735

If there is anybody out there who can make a suggestion on how to correct this, it would be GREATLY appreciated.

Thanks in advance!

guidof
2012-03-24, 09:18
Perhaps you could borrow a different DAC to test if it's your Touch or your DAC that has the problem.

Guido F.

slimmac
2012-03-24, 10:08
Thanks for your response.

I actually borrowed an Arcam rDac and it switches through the various formats with no issue when connected to the analog inputs of the Rotel.
Same cable(s), same songs, no problems.

However, the fact that the Oppo can stream the same files to the Rotel with no issues, makes me wonder what is to blame here. Can a general incompatible between 2 devices exist?
I've scoured the web and see nobody with the same issue.

guidof
2012-03-24, 14:55
Thanks for your response.

I actually borrowed an Arcam rDac and it switches through the various formats with no issue when connected to the analog inputs of the Rotel.
Same cable(s), same songs, no problems.

However, the fact that the Oppo can stream the same files to the Rotel with no issues, makes me wonder what is to blame here. Can a general incompatible between 2 devices exist?
I've scoured the web and see nobody with the same issue.

Perhaps a Toslink glitch on the receiving end of the Rotel?

It IS very odd. Did you try connecting through a digital coaxial cable, or does the Rotel have only Toslink inputs?

Guido F.

slimmac
2012-03-24, 15:22
I tried each of the 3 toslink inputs and each of the 4 co-axial inputs. Same result.
Really makes no sense to me. Must be something wrong with the DAC.
Brutal.

rgro
2012-03-24, 15:43
Just to cover all the bases, have you tried connecting the Touch's analog outs to the Rotel's analog inputs (via standard RCA cables)? If your problem goes away, then you've further isolated things.

slimmac
2012-03-24, 18:10
That's great advice. Thanks.

OK, I just connected the Squeezebox to the analog inputs of the Rotel.
All files played correctly. So, it must be the DAC in the Rotel correct?

rgro
2012-03-24, 19:10
Glad to hear that might be a solution. I don't know if your how your Rotel circuitry is set up internally. It's possible that there are some handshake issues with the Touch's digital signal being fed into the Rotel's internal dac. Others more knowledgeable than I can probably explain why this might be.

If the Rotel has some type of bypass switch or "direct mode"(you can probably find that out in the manual somewhere), you could also go back to your Toslink or coax connection and, if you do have a direct or bypass mode, see if that affects anything. Otherwise, probably best to just stick with using the Touch's analog outs and let the amp do the digitial lifting.