1 have a set of speakers with 1 3.5mm cable coming out of them. is there a splitter i can plug them into so that i can connect multiple devices to the speakers without having to constantly switch the built in 3.5mm jack around?
Its a bit old fashion, but you could use one of the old RCA AV cable switches and just use the appropriate cables to adapt. A cable for male RCA audio to female 3.5 for the speakers and a couple male RCA to male 3.5mm for your audio sources.
I have my speakers and headset plugged in at the same time. I just turn down the speakers when I use the headset using the physical dial on the speakers.
If I understood @Waqas_Khan correctly he wants to connect multiple devices to his speakers, not multiple devices to his PC.
So, this should be the proper item for the job.
They have a 0.5feet and 6feet version.
Be careful when doing this with a 5.1 mobo/card. Some games are funny with how the audio is set up. I did this with Fallout 4, and couldn't hear anything when facing something. In the end I just had to go through the front port on case.