Did not mean to be too negative, but while the plate in the Sunfire Truesub can usually be fixed, the Jr has IC chips that, once gone, make the sub useless until you find a parts unit on ebay. So technically you could know what chip to replace and fix, but getting a working used chip is nearly impossible. They were made for that sub only. I learned this the hard way from buying one on ebay thinking it could be fixed. Eventually VHF confirmed it would be on hold until the part appeared on ebay or Craigslist. After two years of waiting I parted the sub out and moved on.