C2500 dac started acting up

Today all of a sudden I started getting weird issues. A while ago the usb input skipped a few time I rebooted the computer. Today I couldn’t not get it to play my CD transport. It was as if the digital inputs did not work, neither to optical or the coax. I powered it off and unplugged it and the coax worked but I still can not get the optical to work and I used 2 different cables.

Something has gone bad as I was typing this while I was turning the knob to switch it to CD2 as I toggled past inputs I would hear sound impulse from the usb source and when I got to CD2 it would not play and I went back to usb it also would not play. I powered it off and now it plays. So far the CD has not skipped a few minutes into it. The usb other than a few skips has played OK. The demo unit played perfect and the one I returned also played perfect.

CD just skipped 20 min into it.

I did a factory reset and listening to the CD player through coax input 4 it skipped twice within a few minutes. Maybe I need a firmware update?

Oh dear, that doesn't sound good. The biggest risk with a malfunctioning DAC is the potential of sending sudden and loud digital "noise" straight to your speakers which can cause damage if it's loud enough.

It sounds like you've already tried different sources and cables, so something doesn't sound right to me. You could try a firmware update but I can't imagine Mac would send out units malfunctioning that badly that would just need a firmware update to make them work properly. I would inquire with your dealer about the possibility of having them check it out or call McIntosh directly.

This is your second problem with the 2500 is it the same one? Did they exchange or repair it?

The dealer exchanged the unit once for him already.

Yes this is my 2nd one. I guess I'm just Charlie Brown. Chuck at McInosh suggested disconnecting the USB as something in the computer or cable brought down the dac on all inputs. I did that and it skipped within a few minutes on 2 different transports

So if you paly a CD players co-ax digital output into the C2500 does this skip? What software version is installed in your C2500?

thanks,
Ron-C

What about something being wrong with the CD player?

Can you streem to the DAC in the 2500 though the USB port?

Ron I have v1.01

It may be possible that there were issues from the CD and BD drives. The good news is I plugged the USB back in and just completed 3 albums (24/96) from the computer and had no skips.

I’m willing to say it was gremlins and I kind of have an idea how to reset it now but most important is to figure out what I did that pissed it off so much. Something went wrong as I was listening to the USB and it began to skip more often. I then wanted to see if it happen with CDs. I never listen to CDs but this time it didn’t see the player so I switched cables and one of the optical is very old and I don’t know, so far my CD transport the optical out has not worked with either cable but the BD player will.

It took hours and hours to defrag the computer. It runs on a weekly schedule but may have been very fragmented.

Do the C2500 and C50 have the same DAC implementation?

I have similar issue with the USB connection and this from the start.

Once or twice a day the link goes down and for the computer point of view (Linux) the DAC is not there anymore.
Rebooting the Linux box is not solving the problem as it is not a PC problem, rather a DAC issue in my case. A power down/up on the unit solve the problem all the time.
I reported the problem to AC and waiting for feedback from them.

FYI, I did not have issue with the D100.

Brice.

My C2500 DAC has the same issue with my Mac Mini connected via USB. Sometimes when I select a new file to listen to it will not play. The Mac Mini still shows that the C2500 DAC is present but there is no output. It usually happens when the sample rate is different than what I just played for example going from a 24/96 file back to a 16/44.1 file. The only way to fix it is to power cycle the C2500. I have tried different USB cables and I am currently using the Kimber B-Bus with a length of only .5 meter so I do not think it is the cable or the Mac Mini. My music is played through Audirvana Plus in Integer mode.

My C2500 DAC is also connected via optical to my Apple TV and via Coaxial to my Oppo BD player. I have not had any playback problem with either of these devices just the USB.

mdewire,

What you are describing is exactly what I experienced. Thanks for confirming my findings as I was starting to think it was a hardware issue with my Linux box: obviously not if you have the same issue with a Mac Mini.

To be precise, A power down/up on the unit solve the problem all the time, I was speaking about the C2500, not my Linux box. So we are 100% in the same boat.

I traced the kernel messages, and in my case the USB device went away. Simply.
Unplugging and replugging the USB cable does not solve the problem as it appears that the DAC had a crash of some sort.

I hope McIntosh will find the problem asap and will issue a firmware update.

Brice.

This is the reason I refuss to buy a 2ch preamp that incorporates a DAC. I'll sick with the C2300 or my C100 and the D100. At some point the 2500 will not have suport and computers will move farther away.

Case in point.

My iPhone 5 was the first one with 6.0, my service had it set for a hotspot that my iPad could conect to. I changed the pad to the new 7.0 and didn't like it so I did not do the phone. After about 8 months they stoped talking to eachother an I had to change the phone to 7.0.

Really nice McIntosh 40 year old preamps sell for big bucks and sound good. But if we look at any of Mc gear thats 20 years old and has digital in it how are they selling? If we look at computers how have they changed over 20-25 years? Anyone have a floppy disc, fire wire?

Its just a feeling I have but it seems to me most sound formats last about 20 years. LP stereo, cassette, r2r, CD's have stretched the envelope a bit, but as you mention, there is this new digital format with many sub routines. coax, optical,usb, internal DACs exter DACS, what a can of worms.

But then all formats have issues pushing the technological envelope. It wasn't until HO low noise tape and dolby came along that R2R truly became state of the art. How many years passed before Mcintosh brought the MC3500 to fruition. I heard my first Stereo FM broadcast in 1962 or 3. It wasn't until the MR77 came along until I could really enjoy the full capability of FM. It wasn't until my 682Z that I thought cassette was anything but toy format. So I guess I shouldn't shun todays digital live streaming formats. I mean if I could tolerate pops and clicks from LP's I should from digital, too. Don't think So! So I'll stick with CD, SACD, DVD, LP's, and dubbed to CD R2R.

4-2-7 said:

This is the reason I refuss to buy a 2ch preamp that incorporates a DAC. I'll sick with the C2300 or my C100 and the D100. At some point the 2500 will not have suport and computers will move farther away.

Case in point.

My iPhone 5 was the first one with 6.0, my service had it set for a hotspot that my iPad could conect to. I changed the pad to the new 7.0 and didn't like it so I did not do the phone. After about 8 months they stoped talking to eachother an I had to change the phone to 7.0.

Really nice McIntosh 40 year old preamps sell for big bucks and sound good. But if we look at any of Mc gear thats 20 years old and has digital in it how are they selling? If we look at computers how have they changed over 20-25 years? Anyone have a floppy disc, fire wire?

Click to expand...

I feel that DACs seem to break down into two distinct categories... Those which perform standard duties such as those inside and outside of your average CD player which tend to be more time resistant. And those which are part of the hi res computer audio fad, which seem to add yet more upscaling, dejitterizing and higher sample rates every time it rains. The Yamaha CX10000 preamp up there in my avatar contains an early DAC implementation (1987) and to this day, playing any normal digital source through it it would probably blow away most of what's out there.

I do agree that any time you talk about a DAC with a USB input, whatever functionality is provided through that connection will not likely last very long. But I'd rather have the plain old coax and toslink inputs and a good quality basic DAC in there that Mac has blessed and done their magic to than have to go hunt for one of questionable performance. After all, the analog parts of the preamp are still there.

playdrv4me said:

I feel that DACs seem to break down into two distinct categories... Those which perform standard duties such as those inside and outside of your average CD player which tend to be more time resistant. And those which are part of the hi res computer audio fad, which seem to add yet more upscaling, dejitterizing and higher sample rates every time it rains. The Yamaha CX10000 preamp up there in my avatar contains an early DAC implementation (1987) and to this day, playing any normal digital source through it it would probably blow away most of what's out there.

I do agree that any time you talk about a DAC with a USB input, whatever functionality is provided through that connection will not likely last very long. But I'd rather have the plain old coax and toslink inputs and a good quality basic DAC in there that Mac has blessed and done their magic to than have to go hunt for one of questionable performance. After all, the analog parts of the preamp are still there.

Click to expand...

My point is that the DAC in the C2500 should have never been put in it. Mac could have made a add on DAC in a slim line package. Im sure it would sell like hot cakes if it was priced right and below the cost of the D100. What I'm trying to say is it will hinder resale later on for the 2500 owners, like the old CDP and AV units. Not to mention all the owners of old mac Preamps would have a nice little matching DAC with out going the D100 rout. I have a D100 just for the DAC and I just have to ask, Why do I have to buy a Preamp to get a DAC form Mac?

Saying the the C2500 will decrease in value like AV processors isn't really apples to apples. Worst case in X years the DAC in the C2500 becomes outdated, just add an outboard DAC, problem solved and the owner is no worse off than if they had a C2300. If someone owns an AV processor that only supports S-Video, they can't simply add on a unit to add HDMI support, or latest decoders, etc which is why it's a rip and replace. Had I not already owned a C2300, I would've considered a C2500.

Max77 said:

Saying the the C2500 will decrease in value like AV processors isn't really apples to apples. Worst case in X years the DAC in the C2500 becomes outdated, just add an outboard DAC, problem solved and the owner is no worse off than if they had a C2300. If someone owns an AV processor that only supports S-Video, they can't simply add on a unit to add HDMI support, or latest decoders, etc which is why it's a rip and replace. Had I not already owned a C2300, I would've considered a C2500.

Click to expand...

But isn't the C2500 better than the C2300 plus it has a DAC?

Max77 said:

Saying the the C2500 will decrease in value like AV processors isn't really apples to apples. Worst case in X years the DAC in the C2500 becomes outdated, just add an outboard DAC, problem solved and the owner is no worse off than if they had a C2300. If someone owns an AV processor that only supports S-Video, they can't simply add on a unit to add HDMI support, or latest decoders, etc which is why it's a rip and replace. Had I not already owned a C2300, I would've considered a C2500.

Click to expand...

You beat me to it, absolute nonsense that the onboard DAC will affect resale value....
Its an awesome analogue pre-amp in its own right regardless of the DAC.....
There are plenty of inputs, balanced or unbalanced to add a DAC in the future....
The DAC in the C2500 is only a small part of what it can do......

I can't see the DAC will become totally redundant anyway, regardless of where digital audio is going, you will almost certainly be able to use the DAC in any case...
And even though there may be more advanced or "better" DAC's in the future, the sound of the DAC in the C2500, C48,50 or whatever isn't suddenly going to sound like crap just because its been superseded by a newer model....
They are great sounding DAC's and always will be......

4-2-7 said:

But isn't the C2500 better than the C2300 plus it has a DAC?

Click to expand...

It has better analogue performance specifications, but whether that translates to a "better" sound is grounds for subjectivity......

back on the thread topic....

I use 2 x Optical inputs and the USB on my C48, sometimes I have a few problems with the USB input, but its to do with me say using Adirvana, and then watching some clip on Youtube which then can cause some kind of issue where I lose audio, or it jitters, or my computer locks up, and then I have to power cycle the C48.....
But on the whole it is pretty reliable.....and if I am only using Audirvana I don't have problems....
I have never had problems playing different sample rates and bit rates, it just plays whatever I select.......