One other question, does the “spitting/arcing” occur without music playing? If so, this could be caused by dust or particulates trapped between the stator and membrane, it can also manifest itself in form of whistling, buzzing. Generally, this resolves itself on its own. I have experienced this with earlier panel versions although, so far, not with my current Bass Focus 845PX’s.
Another thought, does the music your currently playing contain greater bass energy than that played in the past? If that is the case you might have reached the panels output limits.
Anyhow, I’m only throwing out a few ideas. There may actually be an issue with the panels. That said, the PX panels, as I’m sure Tom will agree, have been the most
reliable of any produced in Soundlab’s history.
You need to swap the back-plates to see if the problem persists. However, if the problem reappears but on the opposite speaker panel the problem may be associated to the backplate.
How many years is “several years” since you have had them? Are they under warranty? It would be very expensive to ship the 945s back to Sound Lab. You might be better off just preparing yourself to do as much diagnostics as possible yourself with the help from the members here.
I have had my speakers for several years and they have been really good. Lately I have been experiencing spitting/arching. I have left the bias on all the time.
I readjusted the bias and the right speaker returned to normal. The left speaker is really twitchy? I have turned down the bias on the right speaker but at times it will still spit. What is causing this and are my panels getting damaged? thanks, the weather is typical spring in the midwest.