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                                                                 EXHIBIT 10.3
                                                                 EXECUTION COPY

                                 THIRD AMENDMENT
                                 ---------------

              THIRD AMENDMENT, dated as of March 4, 2002 (this "Third
                                                                -----
Amendment"), to the Revolving Credit Agreement, dated as of October 7, 1998 (as
---------
amended, supplemented, or otherwise modified from time to time, the "Credit
                                                                     ------
Agreement"), among INSIGHT COMMUNICATIONS OF CENTRAL OHIO, LLC, a limited
---------
liability company organized under the laws of Delaware (the "Borrower"), the
                                                             --------
several banks and other financial institutions or entities from time to time
parties to the Credit Agreement (the "Lenders"), and CANADIAN IMPERIAL BANK OF
                                      -------
COMMERCE, as administrative agent for the Lenders thereunder (in such capacity,
the "Administrative Agent").
     --------------------

                          W I T N E S S E T H :
                          ---------------------

              WHEREAS, the Borrower, the Lenders and the Administrative Agent
are parties to the Credit Agreement; and

              WHEREAS, the Borrower has requested and, upon this Amendment
becoming effective, the Majority Lenders have agreed, that certain provisions
of the Credit Agreement be amended in the manner provided for in this Third
Amendment.

              NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein, the parties agree as follows:

              1.  Definitions. Unless otherwise defined herein, terms defined
                  -----------
in the Credit Agreement shall have their defined meanings when used herein.

              2.  Amendment to Section 1.1 of the Credit Agreement. Section
                  ------------------------------------------------
1.1 is hereby amended by (a) adding thereto the following definition in its
appropriate alphabetical order:

              ""Insight Midwest":  Insight Midwest, L.P., a limited partnership
                ---------------
         formed under the laws of Delaware."

and (b) replacing the definition of "Consolidated Fixed Charge Coverage Ratio"
with the following:

              ""Consolidated Fixed Charge Coverage Ratio": for any period,
                ----------------------------------------
         the ratio of (a) the sum of Consolidated Operating Cash Flow for such
         period and the aggregate amount of capital contributions received in
         cash by the Borrower during such period to (b) Consolidated Fixed
         Charges for such period."

              3.  Amendment to Section 2.1(c) of the Credit Agreement.  Section
                  ---------------------------------------------------
2.1(c) of the Credit Agreement is hereby amended by replacing the contents
thereof in their entirety with the following:

              "(c) The Revolving Commitments shall be reduced (and each
         Lender's Commitment shall be ratably reduced) on consecutive quarterly
         dates, commencing on March 31, 2003, by the amount set forth opposite
         each date below:

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                                                                              2

Date                                           Amount
----                                           ------

March 31, 2003                              $1,250,000
June 30, 2003                               $1,250,000
September 30, 2003                          $1,250,000
December 31, 2003                           $1,250,000
March 31, 2004                              $6,666,666.66
June 30, 2004                               $6,666,666.67
September 30, 2004                          $6,666,666.67"

              4.  Amendments to Section 7.1 of the Credit Agreement.  (a)
                  -------------------------------------------------
Section 7.1 of the Credit Agreement is hereby amended by deleting the table
contained in paragraph (a) of such Section in its entirety and substituting, in
lieu thereof, the following:
                                                         Consolidated Senior
              "Period                                      Leverage Ratio
               ------                                      --------------

January 1, 2001 to September 29, 2001                      1.25 to 1.00
September 30, 2001 to December 31, 2001                    1.30 to 1.00
January 1, 2002 to December 31, 2002                       1.25 to 1.00
January 1, 2003 to September 30, 2004                      1.00 to 1.00"

              (b) Section 7.1 of the Credit Agreement is hereby amended by
deleting the table contained in paragraph (b) of such Section in its entirety
and substituting, in lieu thereof, the following:

                                         Consolidated Interest
"Fiscal Quarter                            Coverage Ratio
---------------                            --------------

June 30, 2001                               1.15 to 1.00
September 30, 2001                          1.15 to 1.00
December 31, 2001                           1.25 to 1.00
March 31, 2002                              1.25 to 1.00
June 30, 2002                               1.25 to 1.00
September 30, 2002                          1.25 to 1.00
December 31, 2002                           1.25 to 1.00
March 31, 2003                              1.50 to 1.00
June 30, 2003                               1.50 to 1.00
September 30, 2003                          1.50 to 1.00
December 31, 2003                           1.50 to 1.00
March 31, 2004                              1.50 to 1.00
June 30, 2004                               1.50 to 1.00
September 30, 2004                          1.50 to 1.00"

              (c) Section 7.1 of the Credit Agreement is hereby amended by
deleting paragraph (c) of such Section in its entirety and substituting, in
lieu thereof, the following:

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                                                                              3

              "(c) Consolidated Fixed Charge Coverage Ratio.  Permit the
                   ----------------------------------------
         Consolidated Fixed Charge Coverage Ratio for any period of four
         consecutive fiscal quarters of the Borrower ending with any fiscal
         quarter set forth below to be less than the ratio set forth below
         opposite such fiscal quarter:

                                        Consolidated Fixed
Fiscal Quarter                         Charge Coverage Ratio
--------------                         ---------------------

September 30, 2001                         1.00 to 1.00
December 31, 2001                          1.00 to 1.00
March 31, 2002                             1.00 to 1.00
June 30, 2002                              1.00 to 1.00
September 30, 2002                         1.00 to 1.00
December 31, 2002                          1.00 to 1.00
March 31, 2003                             1.00 to 1.00
June 30, 2003                              1.00 to 1.00
September 30, 2003                         1.00 to 1.00
December 31, 2003                          1.00 to 1.00
March 31, 2004                             1.00 to 1.00
June 30, 2004                              1.00 to 1.00
September 30, 2004                         1.00 to 1.00;

         provided, that the Borrower shall not be required to comply with the
         --------
         provisions of this Section 7.1(c) until the earlier of (i) such time as
         the provisions of Section 7.7(a)(iii) shall have been rendered
         inoperative in accordance with the proviso thereto or (ii) such time as
         the aggregate amount of Capital Expenditures made pursuant to Section
         7.7(a) during any fiscal year shall be funded solely from Consolidated
         Operating Cash Flow."

              (d) Section 7.1 of the Credit Agreement is hereby amended by
deleting paragraph (d) of such Section in its entirety and substituting, in lieu
thereof, the following:

              "(d) Consolidated Pro Forma Debt Service Ratio.  Permit the
                   -----------------------------------------
         ratio of (i) Consolidated Annualized Adjusted Operating Cash Flow for
         any period (a "Test Period") of four consecutive fiscal quarters to
                        -----------
         (ii) Consolidated Pro Forma Debt Service for the immediately succeeding
         period of four consecutive fiscal quarters to be less than (x) 1.20 to
         1.00 for the Test Period ending on June 30, 2001, (y) 1.10 to 1.00, in
         the case of any Test Period ending on September 30, 2001 or December
         31, 2001 or (z) 1.20 to 1.00, in the case of any Test Period ending
         thereafter."

              5.  Amendment to Section 7.7 of the Credit Agreement. Section 7.7
                  ------------------------------------------------
of the Credit Agreement is hereby amended by (a) deleting the table contained
in paragraph (a) of such Section in its entirety and substituting, in lieu
thereof, the following:

"Fiscal Year Ending                           Amount
-------------------                           ------
     2001                                   $27,500,000
     2002                                   $35,000,000
     2003                                   $25,000,000

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                                                                              4

     2004                                  $25,000,000;"

(b) deleting the word "and" immediately prior to clause (ii) and substituting
in lieu thereof, "," and (c) adding immediately prior to the semi-colon at the
end of paragraph (a) thereof, the following:

              "and (iii) the aggregate amount of Capital Expenditures made
         during any fiscal year pursuant to this clause (a) shall not exceed the
         sum of Consolidated Operating Cash Flow for such fiscal year plus the
                                                                      ----
         aggregate amount of capital contributions received in cash by the
         Borrower from Insight Midwest during such fiscal year that are not used
         for other purposes, provided that the Borrower shall be entitled to
                             --------
         cause the limitations provided for in this subclause (iii) to be
         rendered inoperative if (x) it shall deliver to the Administrative
         Agent a notice to such effect (setting forth in reasonable detail the
         computations showing compliance with clause (y) immediately following)
         and (y) it would be in compliance with the provisions of Section 7.1(c)
         as at the end of the then most recently completed period of four
         consecutive fiscal quarters for which the Lenders shall have received
         financial statements pursuant to Section 6.1 (as if the Borrower had
         then been required to comply with such Section 7.1(c) in accordance
         with the proviso thereto)".

              6.  Conditions to Effectiveness. This Third Amendment shall be
                  ---------------------------
effective on the conditions that (a) the Administrative Agent shall have
received counterparts hereof, duly executed and delivered by the Borrower and
the Lenders and (b) no Default or Event of Default shall have occurred and be
continuing on the date hereof after giving effect to this Third Amendment. The
date on which all of the above conditions are met shall be the date of
effectiveness of this Third Amendment (the "Third Amendment Effective Date").
                                            ------------------------------

              7.  Representations and Warranties. In order to induce the Lenders
                  ------------------------------
to enter into this Third Amendment, the Borrower hereby represents and warrants
to the Lenders that the representations and warranties of the Borrower and the
other Loan Parties contained in the Loan Documents are true and correct in all
material respects on and as of the Third Amendment Effective Date (after giving
effect hereto) as if made on and as of the Third Amendment Effective Date
(except where such representations and warranties expressly relate to an
earlier date in which case such representations and warranties were true and
correct in all material respects as of such earlier date); provided that all
                                                           --------
references to the "Credit Agreement" in any Loan Document shall be and are
deemed to mean the Credit Agreement as amended hereby.

              8.  Applicable Law and Jurisdiction. This Third Amendment has been
                  -------------------------------
executed and delivered in New York, New York, and the rights and obligations of
the parties hereto shall be governed by, and shall be construed and enforced in
accordance with, the laws of the State of New York.

              9.  Counterparts. The parties may execute this Third Amendment in
                  ------------
counterparts and all such counterparts taken together shall be deemed to
constitute one instrument. Delivery of an executed counterpart of a signature
page to this Third Amendment by facsimile shall be effective as delivery of a
manually executed counterpart of this Third Amendment.

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                                                                              5

              10.  Successors and Assigns. This Third Amendment shall be binding
                   ----------------------
upon and inure to the benefit of the Borrower and its successors and assigns,
and upon the Administrative Agent and the Lenders and their respective
successors and assigns. The execution and delivery of this Third Amendment by
any Lender prior to the Third Amendment Effective Date shall be binding upon
its successors and assigns and shall be effective as to any loans or
commitments assigned to it after such execution and delivery.

              11.  Continuing Effect. Except as expressly amended hereby, the
                   -----------------
Credit Agreement as amended by this Third Amendment shall continue to be and
shall remain in full force and effect in accordance with its terms. This Third
Amendment shall not constitute an amendment or waiver of any provision of the
Credit Agreement not expressly referred to herein and shall not be construed as
an amendment, waiver or consent to any action on the part of the Borrower that
would require an amendment, waiver or consent of the Administrative Agent or
the Lenders except as expressly stated herein. Any reference to the "Credit
Agreement" in the Loan Documents or any related documents shall be deemed to be
a reference to the Credit Agreement as amended by this Third Amendment.

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              IN WITNESS WHEREOF, the parties have caused this Third Amendment
to be executed and delivered by their respective duly authorized officers as of
the day and year first above written.

                                       INSIGHT COMMUNICATIONS OF CENTRAL
                                       OHIO, LLC

                                       By:_________________________
                                          Name:
                                          Title:

                                       CIBC INC., as a Lender

                                       By:_________________________
                                          Name:
                                          Title: