Troubleshooting Problems

MP1 wont work with either 2.0 or 2.01 EPROM

Started by rnolan

Replies: 3
Views: 3,019

June 15, 2019, 08:48:09 AM
by MarshallJMP

Gain drop

Started by Richie_B

Pages1 2

Replies: 17
Views: 9,149

July 12, 2016, 07:22:55 AM
by MarshallJMP

MP-1 volume drop

Started by revhed666

Pages1 2

Replies: 21
Views: 11,031

May 20, 2016, 08:24:13 AM
by Harley Hexxe

Bass setting not saving

Started by revhed666

Replies: 14
Views: 7,779

March 31, 2014, 09:51:25 PM
by rnolan

4ohm Resistor Across C131 & D38 ?

Started by red2203stack

Pages1 2

Replies: 16
Views: 7,503

January 20, 2019, 04:36:13 PM
by red2203stack

MP-1 got Noisy...

Started by rabidgerry

Pages1 2 3

Replies: 34
Views: 17,655

July 02, 2017, 04:53:43 PM
by MarshallJMP

No Edit Function after replacing battery and eprom

Started by potus2028

Replies: 1
Views: 2,878

October 14, 2022, 09:30:47 PM
by rnolan

Fixed: MP-1 with ALL clip leds lit solid and NO sound (long post)

Started by Pork_Chop

Replies: 2
Views: 2,814

November 12, 2021, 09:17:43 AM
by MarshallJMP

Srange Chorus problem

Started by Pete66

Replies: 2
Views: 2,275

September 26, 2020, 12:43:27 AM
by Pete66

MB-1 no output

Started by peoriashows

Replies: 7
Views: 4,863

July 28, 2018, 11:51:45 PM
by rnolan

ADA MP-1 v1.36 Switches on! Normal background noise there, but no Output!!!!

Started by Pedro

Replies: 14
Views: 5,265

November 24, 2020, 11:43:50 PM
by rnolan

New Member - just got an old MP-1 - no sound - it does turn on

Started by Overtone85

Replies: 1
Views: 3,011

October 30, 2018, 01:03:45 PM
by MarshallJMP

MP-1 MIDI not working

Started by niksa

Replies: 11
Views: 8,920

January 10, 2021, 06:30:02 AM
by MarshallJMP

Extreme hiss and microphonic V1 tube circuitry

Started by NeverAfter

Pages1 2

Replies: 19
Views: 10,989

May 06, 2016, 10:33:18 AM
by rnolan

MP-1 A channel much quieter than B

Started by Mxzx

Pages1 2 3

Replies: 31
Views: 16,010

February 12, 2014, 06:32:21 PM
by El Chiguete

MP1 - Developed very loud hum on tube settings

Started by MR THUD

Replies: 8
Views: 3,623

August 29, 2022, 11:38:14 AM
by MarshallJMP

ADA MP1 - Tube Board Problem and Resolution.

Started by MR THUD

Replies: 2
Views: 3,409

November 12, 2021, 09:19:51 AM
by MarshallJMP

MP1 Tube board issues, like am radio

Started by monty

Pages1 2

Replies: 20
Views: 13,423

January 22, 2016, 12:35:39 AM
by tomy

LED Issue MP1

Started by Mojave

Replies: 4
Views: 8,594

December 31, 2023, 12:47:45 PM
by Mojave

Solid State Clean Gets Nasty

Started by Moff40

Replies: 5
Views: 2,774

August 29, 2022, 09:34:51 PM
by Moff40