Buzzing through speaker's tweeters - PrimaLuna Dialogue Two Integrated


Hi Everyone,
I have a PrimaLuna Dialogue Two integrated amp that had all its tubes replaced in Jan. 2019.  Last night I noticed buzzing through my speaker's tweeters when using the Aux 1 input (from Audible Illusions phonostage).  I had not started playing any records and the buzzing increased when I moved up the volume knob.  It would decrease when lowering the volume.  I swapped to the CD input and turned on the SACD player, dead silent.  I swapped my AI phono to a solid state phonostage, but nothing changed.  Still got the buzzing at about the same intensity.  I even moved the RCAs to Aux 2 and still the buzzing.

I emailed PrimaLuna but hope that maybe someone on the forum may know what is causing this and how to fix?
Thanks!
128x128kaloman
Sounds like your problem is the AI preamp, not the Prima Luna.  Check to see if the tubes are seated right in the AI preamp.  The phono tubes in the AI are the two on the left.
That’s what I initially thought until I swapped the AI out with my other phonostage.  The buzzing was still there.
The fact that you can change the volume of the buzz suggests to me that your problem is not the Primaluna. The volume control attenuates the incoming signal so the problem is upstream from the Primaluna. Since both phono stages that you are using create the same buzz it suggests to me that your problem may be with your cartridge or cabling from your turntable or turntable motor. Just a WAG though.
AS @newbee said, check cartridge headshell and tonearm wires. Phono ground and power to turntable for any grounding issues. Also ensure there is no routers, wireless or cable boxes close to the amps.
Some good advice above it absolutely sounds like RFI I had a similar issue recently high frequency crackling from both tweeters. I traced it to a router/modem I had recently moved to the living room near my system.
Same problem, my problem seems to be a bad turntable cable, catching rfi.
 
Very annoying also that I'm near radio broadcast towers, sometimes that's in there too, sporadically.