From your description Id say the motor on your Lux is very close to catching fire and if it was me, I wouldnt be using it any more. Take it to your closest reputable specialist coffee service agent and see if they can have the motor repaired for you, or at least give you a quote as it may not be worth repairing with the cost of labour so high these days.
If you live close to a Trade TAFE College, you might be able to convince the Electrical Trade Instructor(s) to let the Motor Winding Apprentices have a go at fixing it for you as part of a practical training exercise. This can sometimes be a less expensive option than going to an experienced repairer. Anyway, the crux is that the motor is not long for this world so its either going to have to be repaired or scrapped.
With small grinders like the Lux, this scenario is always close to hand because the small motors driving the gearboxes in these machines are not rated for very long operation.... Maybe 30 seconds On then 60 seconds Off or somewhere in this neighbourhood. They are really only designed to grind a single espresso at a time, cool down for a while then ready to grind another single espresso. Theyre not up to grinding say 250g of coffee at a time to fill up bags for friends and relos.... You need a substantial grinder for this sort of duty.
All the best mate and I hope you can get it repaired economically,