yes i can get into download mode.
ive tried earlier today, and the other numerous times in the past and yet it always does that. yet, when i flash cm10.x, it doesnt do that at all. but the sound doesnt work when on jelly bean.
its the at&t variant.
before i did the heimdall earlier today, cwm did mention that the sd-ext couldn't be mounted, and there was no app2sd partition found.