ASP.NET Timer in ASCX Control embedded in ASPX Page Postback - asp.net

Question

I have an ASCX-Control which indecates an Timer, a Label and an updatepanel.
My Timer is not in the Updatepanel.
Every 5 seconds the timer is ticking and read data out of mysql-DB to count the number of new messages and write the number in an label.
In my ASPX Page I embedded the ASCX-Control. The Control is outside of an updatepanel in my ASPX-Page. When the timer in the ASCX-Control is Ticking, the Page is doing an Postback. The problem is, we lose the focus of the current control.
Heres the ASCX-Control:
<%# Control Language="vb" AutoEventWireup="false" CodeBehind="badgeIcon.ascx.vb" Inherits="Test.badgeIcon" %>
<link href="css/badgeIcon.css" type="text/css" rel="stylesheet" />
<asp:UpdatePanel ID="upMsg" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<div id="divIconMsg" runat="server">
<asp:ImageButton ID="iconMsg" runat="server" ImageUrl="~/Resources/iconErinnerung.svg"></asp:ImageButton>
<div id="divMsgCount" runat="server" Visible="false">
<asp:Literal ID="cntMsg" runat="server" Text='0' />
</div>
</div>
</ContentTemplate>
</asp:UpdatePanel>
<asp:Timer ID="tiTimer" runat="server" Interval="5000"></asp:Timer>
ASPX-Page indicates ASCX-Control:
<asp:UpdatePanel ID="upSuche" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<div id="suche" runat="server">
<div id="divImgSuche" runat="server">
<asp:ImageButton ID="imgSuche" runat="server" ImageUrl="~/Resources/IconSuche.svg"></asp:ImageButton>
</div>
<asp:TextBox ID="tbSuche" runat="server" placeholder="Suche"></asp:TextBox>
<div id="divImgSucheClear" runat="server">
<asp:ImageButton ID="imgSucheClear" runat="server" ImageUrl="~/Resources/btnclose.svg"></asp:ImageButton>
</div>
</div>
</ContentTemplate>
</asp:UpdatePanel>
// ASCX-Control with Timer
<uc1:badgeIcon runat="server" id="badgeIcon" />
tbSuche in ASPX-Page loses the focus.
Hope you can help me, thanks.