Cutting Voltage / Gain from DAC directly? volume

Hi,
I am looking at a friends custom DAC kit and its got about 2.0 volt output.

This is some pretty high gain once run thru a preamp. Does not want to have to mod the preamp gain as this would effect the gain on analog sources feeding it too universally.

I am looking for a way to reduce this things output by probably close to 30% or so without of course going to a passive volume or something hooked to the output jacks, and of course do not want to effect the sonic integrity of the unit.

It sounds perfect, just don't want the gain so high as it gives very little volume control control thru the main system, meaning you can not turn the knob to accurately especially by the remote in the preamp without rather large changes in gain.

This is only thru the DAC, all other sources are great.

This unit from what I can see has a dual amp opamp per channel output, we threw a couple different types just because we had them from some other gear which worked perfectly but very little changes in gain, but did change the sound. We only tried just to see what would happen and if it would directly soften up the output a little.

Anyway its a Cirrus like CS4398 dac chip I believe? I know we could to in and solder up a digital volume board directly to the dac and have it control it, but not much space to mount it etc... And its unnecessary as in this project not looking to have a variable volume, just a single clean way to cut the gain on the output or input without effecting the frequency response and sound?

I guess there is some ways to do some parallel / series style resistor stacks, but asking for some other options as doing that seems we might as well just put a variable volume control on the outputs doing the same thing vs. fixing the volume with a couple standard resistors.

Anyway any ideas I am sure it can be done, some units do come with switches internally that can change gains on some higher end units, I have seen a wadia and a few others that do this with like a 1 volt, 2 volt, 4 volt type output. I don't know where to get a part or where to hook this thing up so any help appreciated!

Oh and there is the Cirrus receiver chip in this thing too, its the popular model used in almost everything I have seen, don't remember the number like a CS8486 or something, not sure if it can be done there on the input or somewhere at the output, all chips in this dac are on removable pin boards, including the DAC and receiver so access is pretty much unlimited.

Thanks