OK so it's not the HD on this occasion - maybe! But don't discount the advice though. Do defrag at least weekly. Premiere can get 'very upset' if you don't and can cause this type of problem.

Also, a word of advice, Adobe do not support external and network HDDs for premiere. You might do better to work on a local drive and use the external one as a holding area for non-current work. Probably will never prove a problem - just not supported is all.

Like Marc, I suspect the issue is the bitrate. I know enough that this can cause probs but not (close to) enough to know how to remedy it and/or prove it is the problem.

Might be as simple as resample in Audition or something.

Let us know how it all goes.

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