Ultralite mk3 Buzzing and probable ground issue

Moderator: James Steele

Forum rules
Discussion related to installation, configuration and use of MOTU hardware such as MIDI interfaces, audio interfaces, etc. with Windows
Post Reply
bartak101
Posts: 7
Joined: Sat Nov 03, 2012 4:45 am
Primary DAW OS: Unspecified

Ultralite mk3 Buzzing and probable ground issue

Post by bartak101 »

Hi there,

My Ultralite mk3 has recently developed a buzz that appears to emanate from the area around where the power adapter plugs in. I run off USB so require the 15v power supply. The adapter also runs hot.

This issues seems to also be effecting the audio path. The other night I was sending out from the sound card, into a DAV BG1u, via a Radial DI. There was obvious distortion/buzz that actually appeared to get quieter as I applied more gain on the preamp. This leads me to think this may be a grounding issue.

I'm in the UK. So almost all my gear is on three pronged adapters or IEC plugs. I have borrowed a PAT tester and will check all my outboard's grounds this weekend, but it seems pretty obvious to me that the Motu is the culprit owing to the audible noise coming out of its rear.

Has anyone had a similar issue? I've got a horrible feeling its the unit's transformer or related circuitry and will have to send it in for work. I read that that can take three weeks and I have a lot of work on at the moment.

Thanks for now.
User avatar
mikehalloran
Posts: 15134
Joined: Sun Jan 25, 2009 5:08 pm
Primary DAW OS: MacOS
Location: Sillie Con Valley

Re: Ultralite mk3 Buzzing and probable ground issue

Post by mikehalloran »

This has been reported before. You'll have to do a search to find it. I don't recall the outcome.
DP 11.31; 828mkII FW, micro lite, M4, MTP/AV USB Firmware 2.0.1
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
Post Reply