Does anyone know when do manufacturers typically put out new models in headunits and speakers??? im talking in general here, no specific manufacturer

Bout once a year, when the model numbers change :D I really have no idea haha

in general depends on their contracts with suppliers...

Lots of new shit will come out in the next two months. CES is being held in a fortnight and many new products will be showcased/launched.

i was thinking of buying a new headunit soon, so i think it will be a better idea just to wait a few months and get the new ones

or wait a few months and buy last years models for cheaper. Most of the time the new models only have cosmetic differences. The features are the same a lot of times.