Dell seemingly cannot fix the XPS 15 9570's DPC latency issues
Another missed self-imposed deadline, well done Dell. Over two weeks ago, Frank Azor stated the following on Twitter:
New BIOS to solve most of the other root causes is in development and testing. Working to get it published within [the] next 14 days.
Perhaps unsurprisingly, Dell has failed to meet that timeframe, on which we previously reported. The company has issued no new BIOS revision at the time of writing and has not fixed the DPC latency issues that it said it would. For those who have not read our previous articles, DPC, or Deferred Procedure Call, allows drivers to activate tasks and the system to prioritise them. However, buggy or poorly written drivers can hog resources by making numerous DPC instructions, which can cause audio stutters and glitches as the system struggles to prioritise audio playback over multiple instructions from other sources.
The company has released updated versions of both the Realtek USB Audio and High Definition Audio drivers in the last month, but people are still complaining of experiencing DPC latency issues on their XPS 15 9570s. In response, Dell has since issued the following statement:
Our engineering team is working on identifying all the root causes/subsequent solutions for this issue.
So, it appears then that Dell has still not ascertained all the reasons behind these latency issues. It is looking more likely that the company is simply stalling for time before it releases a new XPS 15 and abandons support for the XPS 15 9570 altogether. We hope that Dell can prove us wrong.