The ornamental design for a telephoneinterfaceunit, as shown and described.
FIG. 1 is a front perspective view of the telephone interface unit of the present invention;
FIG. 2 is a top view of the telephone interface unit of the present invention;
FIG. 3 is a left side view of the telephone interface unit of the present invention;
FIG. 4 is a right side view of the telephone interface unit of the present invention;
FIG. 5 is a bottom view of the telephone interface unit of the present invention;
FIG. 6 is rear view of the telephone interface unit of the present invention;
FIG. 7 is a front view of the telephone interface unit of the present invention;
FIG. 8 is a view perpendicular to the front face of the telephone interface unit of the present invention; and,
FIG. 9 is a rear perspective view of the telephone interface unit of the present invention.
The broken line showing of the telephone interface unit is included for the purpose of illustrating portions of the article and forms no part of the claimed design.