Fresh Set of Eyes

Do you ever feel like you need a fresh set of eyes to look at something so that you can get a new perspective?

This is exactly how I feel with one of my projects at work. I've been on this project since I started with the company over 7 years ago. As of late, we have had some issues creep up that were things I never saw in the past. I've been investigating possible causes and solutions, but haven't found success yet.

I've consulted with others to get their opinion on the situation. In some cases, people are telling me I need start from scratch and develop a whole new process to fix the problem (hard to do when this product is so mature and when I am basically the only resource). In other cases, I need someone else with more expertise to do a more thorough investigation to prove that it is nothing they are doing that could be causing the problem. This typically results in no work done because they brush it off as not their problem or priority.

I feel like I've done all I can and I've looked for all the possible solutions, but I just can't find the one that will fix the problem. I  feel like I'm the only one fully invested in this project. I feel a bit burned out on all the problems. I feel like I need a fresh perspective.

How do you find a fresh perspective when looking at a problem for what feels like forever with no readily apparent solution? 

Do you look to others or do you have a strategy to find your own fresh perspective?