Problems with my DUAL 1249

[PGIO]

Hi, I'm new here.
I've got some problems with my old turntable Dual-1249 . In effect I haven't used it for a long time, anyhow in these days I've bought a new stylus and I tried to play my old vynils. When I switched on my turntable after having connected it to my digital amplifier trough a preampli/analog-digital converter, I experienced two kinds of problems:
the first one is that the left channel was mute (I've inverted the plug L/R and it seem to be a problem related to the turntable output, but what?). Secondly my Dual doesn't shut-off both in manual than in automatic mode.
I've read in the service manual that the cause may be in a capacitor in the switch power unit. But it is difficult to find it (for me). At the moment I've no mean to buy a new turntable. Any idea to help me?
Thank-you in advance
bye
Paolo (from Venice)

[mrow2]

Everything needs to be carefully cleaned, from the little cartridge wire connectors to the cartridge holder contacts, contacts in the tonearm, and cable connectors. Cable should be checked for continuity too. These connections become tarnished and eventually won't make good connections. Small dental hygene tools combined with electronics contact cleaner, also isopropyl and rubber erasers all have functions here to clean the surfaces. The tiny wire connectors in the cartridge holder can break and will need careful repair if they do.