All of a sudden getting a hum in my system?

Sorry for the late response but I have not visited Audiogon in awhile.
I sent the Chinook to Manley and they said the problem was with a capacitor.So with insurance that cost me over $90.00 which is not covered by the warranty to have a capacitor replaced.
I got the Chinook back and it was working alright for awhile.But several times recently while playing a record I am getting some loud pops followed by a loud hum from my speakers.Also several times recently I have noticed speaker oscillation as soon as the needle hits the record,this is before the music starts.
Is my Chinook a lemon?

Loud pop's and hums usually are related to tubes and/or caps. With you unit's history it is probably caps. FWIW, it is recommended for any tube component user to have a spare set of tubes on hand so he can rule out tubes issues when problems occur. BTW with most tube problems you only hear the problem in one channel unless the bad tube is shared by both channels. It's under warranty so Manley should handle for you (again).

Re speaker oscillation - I assume that what you mean is that the woofer cone is moving in and out substantially but there is no apparent increase in bass. If that is so the typical problem is a mismatch of cartridge and tone arm (mass v compliance) which would be best resolved by getting the appropriate stuff in the first place, although it is possible to get a subsonic filter that would help reduce it. It is also possible to get a device to damp tone arm movement that might help. I had this problem many years ago and I traced it to the fact that my arm had damping capacity built in, all I had to do was add some fluid to the oil well.

Hope that helps a bit.

How weird I have the same problem. I am using a ZU/DL103 with a modified RB250 and have a hum problem when arm is grounded to the chassis ground of the Manley Chinook. However when i disconnect the ground the hum goes away but have a occasional loud pop.

Manley sent me a new Chinook a year ago.After about a month I started getting an occasional pop and hum. It has occurred three times in the last three weeks so I e-mailed the Manley service department today.My first experience with tubes has been a frustrating one,but I do love the sound.My advice would be to e-mail ManleyLabs.com. Good Luck!