I'm no expert (recently bought a used Trib L2500 myself) but after playing it all weekend I found 2 things that I would've looked for had I bought it in person. I bought it off Ebay.
1.) Flick all the switches and turn all the knobs and play it like you would live or on recording. Make sure ALL the settings work and you don't get any weird results when playing each setting. I get some weird signal loss\distortion sometimes when I switch from Active to Passive mode. Not sure what it is but if I flick the switch through all 3 settings, it corrects itself and I get regular full output in all modes.
2.) Make sure the output jack is working solid. There are posts about output jacks going bad. This might be part of my problem in item 1 but not sure.
Other than that, mine is good to go!
Mine didn't have this problem, but check the bridge to make sure the mounting screws are secure, especially if it's strung through bridge only. There are posts here that warn of the bridge screws being pulled out of the body via string through bridge.
I read every thread I could find on these basses before I bid on my Tribute L2500 a few weeks ago and the only 2 glaring issues that seemed common or expected were the output jack and the bridge.
Good luck and post a pic if you get it!
