External inputs enabled while sampling?

I have a Roland SP-404 and it has the most annoying barrier ever - when I samle directly into it through either the mic or a MIDI in, I can't play other samples.

I don't necessarily want to sample everything together (the MIDI and existing sampes) I just want to be able to hear an existing sample for reference, instead of trying to find the bpm and record it with a metronome, syncing the two samples later.

It's just a nusance to have to export the existing sample and play it through some other source while I sample something else in time with it.

Do any Akai's have this problem too?
I can't find any information on it.

<3

If I get your question correctly, yes it is possible to play back the sequence whilst recording. I have used the MPC to do multi tracking for a 16 bar loop (guitar, vocals etc).

I'm not sure about individual sample triggering though. But definately you can play a sequence while recording in the mpc500.

i can attest to the mpc500's ability to trigger samples in record mode.