Sorry. I'm wondering a few things about your audio issue. It sounds like a performance issue. I think I need more info.
First. You mentioned one workstation.
How many people is "we?"
What do you mean by this?
Do they have a computer too? If so, what kind of computer do they have?
Is this "network drive" connected to more than one workstation?
Second. Which format is being edited with?
Which camera did the footage come from?
Were proxies or transcodes made when you started the project?
Third. Has this "network drive" ever worked when shuttling audio at high speed?
If so, what changed since then?
If not, what makes you think this system should not have this audio issue?
Sorry for all the questions. I am just trying to get a clearer picture on what you have there, what material you are working with, how many streams you are editing, the throughput per stream that you need, and what needs to be done, in general. Unfortunately, there are not many resources for troubleshooting network attached drives, SANs, NAS, etc. I do hope I can help, though.
1)Only one person access the file at a time. Single worksation with 10G is accessing the file at time. We are using Dell-EMC Isilon storage. There are multiple Adobe NLE workstation that are connected to the storage as attached image. There is no issue when multiple user accessing the storage as it as very high throughput(40,000Mbs). We use SMB protocol to access the file
2) Material comes from multiple providers and also our recording ports. The format we used is Quicktime (MOV) or MXF. The codec we use is XDCAM HD 422 50Mbs.
3)It was not an issue previously as we don’t fast forward during the editing process. Recently only we have requirement to do fast forward during editing. There is no issue with the video during the forward, only the audio.
Intel HD Graphics 630 1536 MB I made 1080 Apple Pro Res 422 proxies from 4K Photo JPEG footage from a Canon EOS 1dx mark iii and I while I'm playing clips inn fast forward frome the Timeline I get a few seconds of audio but then it goes off.