[Jukebox-list] Seeburg C Low Volume

Amp rebuilt . good tubes, etc.  Volume still too low. With ohmeter I am reading @ 3.5 Megohms between the center conductor and shield ground on the PU input cable that plugs into the amp. Is this normal?  I would think It should read totally open. Could this resistance be bogging down my volume? Not sure of cartridge status.  thanks for any help .