Scrum only provides three roles: Scrum Master, Product Owner, and Development Team. No other roles are defined in Scrum. Since Scrum does allow for some elements of each role to be delegated, you may choose to give a name to the role assigned to the person who is delegated certain tasks and this name would be up to your organization.
The Product Owner role is responsible for Product Backlog management, and it sounds like most of these tasks fall squarely into that realm. Specifically, the Scrum Guide says this about the Product Owner:
The Product Owner is the sole person responsible for managing the Product Backlog. Product Backlog management includes:
- Clearly expressing Product Backlog items;
- Ordering the items in the Product Backlog to best achieve goals and missions;
- Optimizing the value of the work the Development Team performs;
- Ensuring that the Product Backlog is visible, transparent, and clear to all, and shows what the Scrum Team will work on next; and,
- Ensuring the Development Team understands items in the Product Backlog to the level needed.
The Product Owner may do the above work, or have the Development Team do it. However, the Product Owner remains accountable.
If issues are being reported from outside the Scrum Team (which consists of the three roles), then those issues have an impact on the Product Backlog. Things like bug reports, changes to existing features, or new feature requests would be new or modified Product Backlog items.
Do note that the Product Owner may delegate some of these responsibilities to the Development Team. Of course, doing this will reduce capacity for the team. However, involving technical people sooner may lead to more well refined Product Backlog Items going into Sprint Planning sessions. This is a tradeoff that the team (or sometimes the organization) needs to make.
One thing that you mention, "communicate and track support" may also fall into the role of Scrum Master. The Scrum Master does provide support to not only the Development Team, but also the Product Owner and the organization. The Scrum Master should be helping the Product Owner find ways to deal with these incoming requests and methods to appropriately manage the Product Backlog, including writing good Product Backlog items. The Scrum Master is also responsible for making sure that any impediments to the Development Team are removed.
All of that definition-of-Scrum aside, you can identify other tasks that need to be done during the course of a Sprint and who will be responsible for handling them. And it's up to you to appropriately identify these roles and find good ways to delegate them, either on a permanent or rotating basis.
Personally, I think that the Product Owner, perhaps with support from one member of the Development Team (perhaps on a rotating basis) and the Scrum Master, should take the lead on these items. Investigating incoming issues and turning them into Product Backlog Items is definitely a Product Owner function, which may be delegated. Working to resolve impediments is definitely a Scrum Master function, which may include appropriate escalation. Tracking support may be a shared responsibility, but I would consider this to be a task that should be done by the Scrum Master to allow the Development Team to focus on development rather than tracking other people's work.