The multilink interface parent config takes precedence over the child interface configs. For example, off a working box...
interface Multilink1
bandwidth 4096
ppp multilink
ppp multilink group 1
!
interface Serial0/0
bandwidth 2048
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1
!
interface Serial0/1
bandwidth 2048
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1
router#show int mu1
Multilink1 is up, line protocol is up
Hardware is multilink group interface
...
MTU 1500 bytes, BW 4096 Kbit, DLY 10000 usec,
reliability 255/255, txload 9/255, rxload 15/255
Encapsulation PPP, LCP Open, multilink Open
Open: IPCP, loopback not set
DTR is pulsed for 2 seconds on reset
Last input 00:00:00, output never, output hang never
Last clearing of "show interface" counters 6d22h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 33
Queueing strategy: fifo
router#show int se0/0
Serial0/0 is up, line protocol is up
Hardware is GT96K Serial
MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,
reliability 255/255, txload 11/255, rxload 20/255
Encapsulation PPP, LCP Open, multilink Open, loopback not set
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 6d22h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair [suspended, using FIFO]
FIFO output queue 0/40, 0 drops
5 minute input rate 166000 bits/sec, 198 packets/sec
5 minute output rate 94000 bits/sec, 196 packets/sec
68017631 packets input, 3149556926 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
71803478 packets output, 69897268 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
router#show int se0/1
Serial0/1 is up, line protocol is up
Hardware is GT96K Serial
MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,
reliability 255/255, txload 11/255, rxload 20/255
Encapsulation PPP, LCP Open, multilink Open, loopback not set
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 6d22h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair [suspended, using FIFO]
FIFO output queue 0/40, 0 drops
5 minute input rate 166000 bits/sec, 198 packets/sec
5 minute output rate 94000 bits/sec, 196 packets/sec
68017905 packets input, 3149426478 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
2 input errors, 2 CRC, 0 frame, 0 overrun, 0 ignored, 1 abort
71804080 packets output, 69968875 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
