New FiiO K5 Pro Dac DAC No Sound [Resolved: RCA to FiiO aux out to KEF aux in]

Core Machine

Nucleus/iMac Pro Roon Control/KEF LSX/FiiO K5 pro dac

Network Details

Kefs / Nucleus both wired via ethernet

Audio Devices


Library Size


Description of Issue

Hi. Feeling dumb but can’t figure this out. Just bought and hooked up via USB to my iMac Pro running latest OS a FiiO K5 Pro Dac as I want to play DSD files thru the KEF speakers. Roon shows the FiiO as end point, track plays, no sound. Chose FiiO for Mac output and Midi output and no sound. Headphones connected work great. What am I missing/not doing here? Any help is much appreciated. Or sleep, sleep might help lol. Thanks

How have you got the fiio connected to the kef?
Assume it’s RCA to 3.5mm aux?

When trying to output to the kef I assume you have the unplugged your headphones from the headphone output?

No I don’t have it connected. The KEF right speaker has one 3.5 aux input? And yes I unplugged the headphones haha. A year or so back I had a Meridien USB Dac and did not need to wire the KEFs? So do I just use one RCA cable from FiiO to KEF input? Thanks so much.

So you run a cable from the Fiio to the KEF which is 2 x RCA (connectted to the Fiio line out) to 1 x 3.5mm (plugged into the KEF master unit input).

Thats what you are doing yes?

I dont see any other way to get a signal between the 2 units otherswise.

No that’s not what I’m doing. Like my first post, I’m just USB right now. The KEF is one 3.5 input the Fiio is 2x RCA. I don’t even have an RCA that is 2/1 ended. But even if I do, won’t that put an analog signal then back to digital? Probably won’t be able to get DSD to the KEFS that way right?

As @ogdens_sliced has said, you will need to connect the K5 to the KEFs by RCA, the K5 doesn’t connect wirelessly which is what I think you are expecting it do?

I guess I thought since Roon was seeing the DAC it would play thru my speakers. So what cable do I need if the DAC has RCA outs and ins and the Kef just has the one Aux in? And will that allow DSD from ROON and DAC or will it be PCM? if PCM than I won’t bother and just use the Dac for headphones. Thanks so much

The LSX is a DSP speaker. Even if you feed it an analog signal it goes through ADC to become digital. Analog from DSD will be digitized to PCM. If you feed it a digital signal, Roon can convert DSD to PCM before sending to it.

Yeah I kinda had a feeling thats what would happen. Someone on an earlier thread said the KEFS could only handle DSD with a DAC. But I had my doubts. When I play DSD files thru Roon to the KEFS they are converted to PCM. So will leave it at that but do have a question: will the KEFS sound better if I do the analog from the FiiO Dac? If so I have plenty of RCA cables but no RCA to Analog but can I just use one end of an RCA Cable to the input of the KEF? Sorry I’m kind of a newbie at connections in the digital world. Thanks so much guys

No contradiction here. DSD is indeed handled by Roon converting it to PCM before feeding the KEF. If you use a DAC, the DSD is handled by the DAC, converted to analog, then back to PCM by the KEF. In both cases you succeed in playing DSD.

In a scenario where DSD is not handled, you get no sound from the KEF because no software or DAC is converting it to a format that KEF can accept.

Please try it and report.

Ok I will get an RCA to Analog cable tomorrow and try it out

Ok. Plugged an RCA to the FiiO aux out to the KEF aux in. Hit AUX on the Kef app, and it is FANTASTIC! Full lossless from 16/44 all the way to DSD !! It’s so good I think I need to fill it in with a small sub I have out in my garage. Very happy sound so great. Thanks everyone