...anybody wanna help? i've had my 303 for just about a year to the day. i bought it used off of ebay, and it worked fine up until about may/june-ish, when this knob started loosening. as you all probably know, the mfx knob controls all output levels during recording, as well as controls all the fx on it- so it's kind of a bitch having to forcefully hold it and push down to keep it at 127, because otherwise it'll randomly jump to different numbers (usually zero). can anyone help please- or at the very least show me where i can get a replacement part/repair or something?
thanks

Also logged back in here to ask this exact same question.
The Ctrl 3 knob AND the Volume knobs have stopped working and either need to be fixed or replaced, but i'm unsure as to whether either can be done?

I've taken some photos of the culprits that aren't working after pulling the unit apart.

Also having the same problem with my Control 3/MFX knob. DIY fixes would be appreciated.

Yup, just been dealing with it. sure would be nice to get that 3rd knob finally fixed. seems alot of us have this problem.

Yeah, I forgot I even posted on here last year...and I've been dealing with the same broken knob since then haha. It's still functional- but as you all know, the CTRL 3 knob controls the overall volume/loudness (whatever you wanna call it) for any particular sample. So when I'm playing a sample (especially trying to trim it down), the volume shoots up to 127 and down to 0 constantly and unpredictably, and sometimes it will go from one extreme, then climb up or down the entire register to the other extreme. I've pretty much retired it at this point, and when I get an SP-404 or something I'm probably gonna just end up using the 303 for auxilliary effects in a live setting. It kinda sucks though, because I have yet to find even a spare parts dealer, let alone someone that can replace the knob for me- because other than that the machine works just as well as it did when I bought it. Oh well...

on this broken sp i have, the mfx is slightly harder to turn at first but becomes loose roughly around 11 o clock on the knob . does it need some lubricating? how could i fix this if i have already opened up my sp?

could anyone of you who had opened up his sp303, tell me if there is any device name found on the knobs or any kind of serial number?
i think the hardest part in replacing the knobs is getting the spare parts.
once you have them it just needs some soldering, am i right ?

iam pretty curious about this topic as well, cause its good to know how to fix your own stuff

this topic deals with this question as well although it´s 404. don´t know if it makes a huge difference.

http://sp-forums.com/viewtopic.php?f=3&t=13594

i opened mine up and it's still open just incase i figure out how to fix it, i don't know how to properly remove these bands connecting the device so i can't help really help u until i disconnect them

pretty sure there are some fixes around on the forum. search for "rotary encoders" Ive done this shit on other equipment and its pretty easy using a soldering iron. This is the part number/place you can buy the sheeeit http://www.mouser.com/ProductDetail/ALPS/RK09K12C0A8K/?qs=sGAEpiMZZMv8dIMJ2cKI/LpeGcQ9e20X

Quick question:

Just got a used sp 303 today and I am having issues with knobs as well. My biggest question concerns using the second knob: When I use the start/stop function and effects, it is really not clear to me if my second knob is functioning at all. When I turn the third knob to edit the end time I see the numbers appear and it cuts fine but when I turn the start knob I don't see numbers and it is really hard to tell if it is chopping the start of the sample.

My Fourth knob is on its way out and I want to repair that but before I order parts and open this magical little box up, I want to know if I need to do the second knob as well.

Thanks in advance I am super new to this board and really happy I found it.

......so i guess nobody ever found a solution to this issue?

i've pretty much just accepted it at this point, and now i just try to do as little trimming or velocity-changing as possible. i've taken it in to a music store where the guy did repairs on the side, and after he soldered the knob he ended up f###ing it up even more because now the knob is securely in place, making the workaround of pressing down on it just right to be able to adjust it nearly impossible. i guess if there's one thing we've all learned from this, it's "don't buy an SP-303" haha... :?