Variax guitars changing models all on it's own is not just a 300 issue, it seems to be a problem with most of the models.

I bought mine used last year, not being satisfied with my Roland/Strat set up. You just can't get the right feel on the Roland when it comes to acoustic guitars.

Knew about the variax guitars, but didn't want to spend that much money on a guitar that had to be ordered. Wanted to try it with my gear - local guitar center does not stock them.

Finally found a 300 on craigslist for $200. I figured it was worth the gamble. Got it down to $160. It had no case, no power supply, and a twisted neck.

Did some neck work, made some adjustments, loaded up some batteries....... Didn't sound too bad. Even if I just used it for acoustic, it was worth the investment.

Brought it to a gig - Now I know why he wanted to sell it!!!!!!

The 300 just starts changing guitar models on it's own. And when it does settle down, Switch positions 1 and 2 are the same, no matter where you set the guitar selector switch.

Figured it eats up batteries, and when they get low, the electronics starts freakin' out. Bought the Power Supply and the foot switch (Sweetwater). Seemed like a good idea to route the guitar to my amp, and the acoustic sounds straight to the PA. Sounded great, but still switched when I used it on a gig (remember the on a gig part)

After reading the forums, I figured it had never been updated, so I bought the Workbench (Sweetwater). Did all the updates, changed some patches, tried some de-tuning. Sounded great, but still switched when I used it on a gig. A-HA. Vibration?  Bad Connections? Cold solder joint?.......

Chances are I play a little harder at a gig, then when I'm in my computer room messin' around with it.

After reading discussions about the random changing problem, I figured it was time open 'er up.

Pulled the pickguard off - 1st thing I noticed, the ground wire to the body was very loose. A VERY small screw, screwed into the body (painted with metallic paint, I assume.) allowed the guitar to act like a shield to the internal circuitry - much like how a laptop (plastic case) is shielded. That connection MUST be tight. Solution - a bigger screw, and took some sandpaper an roughed up the point of contact. DON'T SAND DOWN TO THE WOOD.

Next, when you remove the metal shield (couple of screws on the side), you'll notice some components (look like metal case transistors) that sit VERY close to the shield. I used electrical tape, and taped the entire inside of the shield so that the components can't touch the shield (the shield is ground, 0 volts). There are a couple of ribbon wires you have to detach. They're polarized, so you can't put them back wrong - however, it wouldn't hurt to mark them, or take a picture before you disconnect.

Next, the switch. This was why I came in here in the first place. I took a soldering iron and refreshed all the switch connections to the circuit board. Then I sprayed the s**t out of it with contact cleaner - the good stuff (no lubricant, it attracts dust)

The Pots are sealed, so there's not much you can do with them. Maybe spray the shaft, and hope some cleaner get's in there.

I did this on Sept 10th, and have rehearsed 4 times and gigged 4 times since, and not a single problem.

It has become my exclusive guitar on gigs. Ordering a Warmoth replacement neck next month (if it behaves). The Tele is now my backup.

It even functions properly on batteries. I wonder how many sets of batteries I tossed thinkin' they were dead.

BTW, I'm on the hunt for more used 300's. I have a Strat Body and Tele Body I'd like to transplant them into

AL